VARIANT RNAi

ABSTRACT

Provided herein are RNAi molecules for treating Huntington&#39;s disease. Further provided herein are expression cassettes, vectors (e.g., rAAV, recombinant adenoviral, recombinant lentiviral, and recombinant HSV vectors), cells, viral particles, and pharmaceutical compositions containing the RNAi. Yet further provided herein are methods and kits related to the use of the RNAi, for example, to treat Huntington&#39;s disease.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the priority benefit of U.S. ProvisionalApplication No. 62/561,843, filed Sep. 22, 2017, which is herebyincorporated by reference in its entirety.

SUBMISSION OF SEQUENCE LISTING ON ASCII TEXT FILE

The content of the following submission on ASCII text file isincorporated herein by reference in its entirety: a computer readableform (CRF) of the Sequence Listing (file name: 159792014740SeqList.txt,date recorded: Sep. 20, 2018, size: 19 KB).

FIELD OF THE INVENTION

The present invention relates to variant RNAi molecules. In someaspects, the invention relates to variant RNAi to treat Huntington'sdisease.

BACKGROUND

RNA interference (RNAi) has been shown to be a useful tool for genesilencing in basic research of gene function and shows great promise asa therapeutic agent to suppress genes associated with the development ofa number of diseases. In nature, gene regulation by RNAi occurs throughsmall RNAs known as microRNAs (miRNAs) (Ambros, (2004) Nature431:350-355; Krol et al., (2010) Nat. Rev. Genet. 11:597-610). MicroRNAshave emerged as powerful regulators of diverse cellular processes, andwhen delivered by viral vectors, artificial miRNAs are continuallyexpressed, resulting in a robust and sustained suppression of targetgenes. The elucidation of the mechanisms involved in miRNA processinghas allowed scientists to co-opt the endogenous cellular RNAi machineryand direct the degradation of a target gene product with the use ofartificial miRNAs (see. e.g., US PG Pub. 2014/0163214 and Davidson etal., (2012) Cell 150:873-875).

A hurdle to the clinical development of RNAi is the potential foroff-target silencing where the seed region of the RNAi (typicallynucleotides 1-7 or 1-8) pairs with sequences in non-target mRNAs in the3′ untranslated region (UTR) leading to transcript destabilization.Attempts to reduce off-target silencing include the use of algorithms toidentify candidate seed sequences with high specificity for the targetmRNA with minimal off-target potential (Boudreau R L et al., (2012)Nucl. Acids Res. 41(1):e9) and placing an internal bulge in the guideregion of the RNAi (Terasawa et al., (2011) Journal of nucleic acids2011:131579).

RNAi has been investigated as a therapeutic to treat Huntington'sdisease (HD). HD is an inherited neurodegenerative disease caused by anexpansion of the CAG repeat in exon 1 of the huntingtin gene (HTT). Theresulting extension of the polyglutamine tract in the N-terminal regionconfers a toxic gain-of-function to the mutant huntingtin protein(mHtt). The potential of silencing mHtt expression as a therapeuticstrategy for HD was first demonstrated in a conditional mouse model ofthe disease (Yamamoto et al., (2000) Cell 101:57-66). When theexpression of mHtt was induced in these mice, pathological andbehavioral aberrations became apparent. Subsequent tetracycline-mediatedrepression of the mHtt transgene reversed these abnormalities,indicating that a reduction of mHtt levels allowed protein clearancemechanisms within neurons to normalize mHtt-induced changes. Hence,therapeutic strategies that reduce mHtt levels could potentially haltdisease progression and alleviate HD symptoms. miRNAs that target Httare provided in WO 2016/130589, incorporated herein in its entirety.

All references cited herein, including patent applications andpublications, are incorporated by reference in their entirety.

BRIEF SUMMARY OF THE INVENTION

In some aspects, the invention provides an RNAi comprising a firststrand and a second strand, wherein a) the first strand and the secondstrand form a duplex; b) the first strand comprises a guide region,wherein the guide region comprises the nucleic acid sequence5′-UGGCCGUCCAUCUUGGACCCG-3′ (SEQ ID NO: 1) or5′-AGUCGGUGUGGUUGACAAGCA-3′ (SEQ ID NO:7); and c) the second strandcomprises a non-guide region. In some embodiments, the nucleic the guideregion comprises the nucleic acid sequence 5′-UGGCCGUCCAUCUUGGACCCG-3′(SEQ ID NO: 1) and the non-guide region comprises the sequence5′-CGGGUCCAAGAUGGACGGCCA-3′ (SEQ ID NO:2). In some embodiments, thefirst strand comprises a nucleic acid sequence having about 90% identityto SEQ ID NO:1 or about 90% identity to SEQ ID NO:2. In otherembodiments, the nucleic the guide region comprises the nucleic acidsequence 5′-AGUCGGUGUCGGUUGACAAGCA-3′ (SEQ ID NO:7) and the non-guideregion comprises the sequence 5′-UGCUUGUCAACCACACCGACU-3′ (SEQ ID NO:8).In some embodiments, the second strand comprises a nucleic acid sequencehaving about 90% identity to SEQ ID NO:7 or about 90% identity to SEQ IDNO:8. In some embodiments of the above embodiments, the first strand andthe second strand are linked by means of RNA linker capable of forming aloop structure. In some embodiments, the RNA linker comprises from 4 to50 nucleotides. In some embodiments, the loop structure comprises 4 to20 nucleotides. In some embodiments, the RNAi comprises 5′ to 3′ thesecond strand, the RNA linker, and the first strand. In someembodiments, the RNAi comprises 5′ to 3′ the first strand, the RNAlinker, and the second strand. In some embodiments, the RNAi comprisesthe nucleic acid sequence of SEQ ID NO:4 or SEQ ID NO:10. In someembodiments, the RNAi comprises a nucleotide sequence about 90%identical to the nucleotide sequence of SEQ ID NO:4 or SEQ ID NO: 10. Insome embodiments, the RNAi is a small inhibitory RNA (siRNA), a microRNA(miRNA), or a small hairpin RNA (shRNA). In some embodiments, the RNAitargets RNA encoding a polypeptide associated with Huntington's disease.In some embodiments, the polypeptide is huntingtin. In some embodiments,the huntingtin comprises a mutation associated with Huntington'sdisease.

In some embodiments of the above aspects and embodiments, the inventionprovides an expression construct comprising nucleic acid encoding theRNAi of any one of claims 1-16. In some embodiments, the nucleic acidencoding the RNAi comprises a miRNA scaffold. In some embodiments, thenucleic acid encoding the RNAi is operably linked to a promoter. In someembodiments, the promoter is selected from a cytomegalovirus (CMV)immediate early promoter, an RSV LTR, a MoMLV LTR, a phosphoglyceratekinase-1 (PGK) promoter, a simian virus 40 (SV40) promoter, a CK6promoter, a transthyretin promoter (TTR), a TK promoter, a tetracyclineresponsive promoter (TRE), an HBV promoter, an hAAT promoter, a LSPpromoter, a chimeric liver-specific promoter (LSP), an E2F promoter, atelomerase (hTERT) promoter; a cytomegalovirus enhancer/chickenbeta-actin/Rabbit β-globin promoter (CAG) promoter, an elongation factor1-alpha promoter (EFl-alpha) promoter, a human β-glucuronidase promoter,a chicken β-actin (CBA) promoter, a retroviral Rous sarcoma virus (RSV)LTR promoter, a dihydrofolate reductase promoter, and a β-actinpromoter. In some embodiments, the expression construct furthercomprises a polyadenylation signal. In some embodiments, thepolyadenylation signal is a bovine growth hormone polyadenylationsignal, an SV40 polyadenylation signal, or a HSV TK pA.

In some embodiments, the invention provides a vector comprising theexpression construct of any one of the embodiments described herein. Insome embodiments, the vector is a recombinant adeno-associated virus(rAAV) vector, a recombinant adenoviral vector, a recombinant lentiviralvector or a recombinant herpes simplex virus (HSV) vector. In someembodiments, the vector is a recombinant adenoviral vector. In someembodiments, the recombinant adenoviral vector is derived fromAdenovirus serotype 2, 1, 5, 6, 19, 3, 11, 7, 14, 16, 21, 12, 18, 31, 8,9, 10, 13, 15, 17, 19, 20, 22, 23, 24-30, 37, 40, 41, AdHu2, AdHu 3,AdHu4, AdHu24, AdHu26, AdHu34, AdHu35, AdHu36, AdHu37, AdHu41, AdHu48,AdHu49, AdHu50, AdC6, AdC7, AdC69, bovine Ad type 3, canine Ad type 2,ovine Ad. or porcine Ad type 3. In some embodiments, the recombinantadenoviral vector is derived from adenovirus serotype 2 or a variant ofadenoviral serotype 5. In some embodiments, the vector is a recombinantlentiviral vector. In some embodiments, the recombinant lentiviralvector is derived from a lentivirus pseudotyped with vesicularstomatitis virus (VSV), lymphocytic choriomeningitis virus (LCMV), Rossriver virus (RRV), Ebola virus, Marburg virus, Mokala virus, Rabiesvirus, RD114 or variants therein. In some embodiments, the vector is arHSV vector. In some embodiments, the rHSV vector is derived from rHSV-1or rHSV-2.

In some embodiments of the above aspects and embodiments, the vector isa rAAV vector. In some embodiments, the expression construct is flankedby one or more AAV inverted terminal repeat (ITR) sequences. In someembodiments, the expression construct is flanked by two AAV ITRs. Insome embodiments, the AAV ITRs are AAV1, AAV2, AAV3, AAV4, AAV5, AAV6,AAV7, AAV8, AAVrh8, AAVrh8R, AAV9, AAV10, AAVrh10, AAV11, AAV12,AAV2R471A, AAV DJ, a goat AAV, bovine AAV, or mouse AAV serotype ITRs.In some embodiments, the AAV ITRs are AAV2 ITRs. In some embodiments,the vector further comprises a stuffer nucleic acid. In someembodiments, the stuffer nucleic acid is located upstream or downstreamof the nucleic acid encoding the RNAi. In some embodiments, the vectoris a self-complementary rAAV vector. In some embodiments, the vectorcomprises first nucleic acid sequence encoding the RNAi and a secondnucleic acid sequence encoding a complement of the RNAi, wherein thefirst nucleic acid sequence can form intrastrand base pairs with thesecond nucleic acid sequence along most or all of its length. In someembodiments, the first nucleic acid sequence and the second nucleic acidsequence are linked by a mutated AAV ITR, wherein the mutated AAV ITRcomprises a deletion of the D region and comprises a mutation of theterminal resolution sequence. In some embodiments, the inventionprovides a cell comprising any of vectors (e.g., rAAV vectors) describedherein.

In some embodiments of the above aspects and embodiments, the inventionprovides a viral particle comprising any of the vectors describedherein, wherein the viral particle is an AAV particle encapsidating therAAV vector, an adenovirus particle encapsidating the recombinantadenoviral vector, a lentiviral particle encapsidating the recombinantlentiviral vector or an HSV particle encapsidating the recombinant HSVvector. In some embodiments, the viral particle is an adenovirusparticle encapsidating the recombinant adenoviral vector. In someembodiments, the adenovirus particle comprises a capsid from Adenovirusserotype 2, 1, 5, 6, 19, 3, 11, 7, 14, 16, 21, 12, 18, 31, 8, 9, 10, 13,15, 17, 19, 20, 22, 23, 24-30, 37, 40, 41, AdHu2, AdHu 3, AdHu4, AdHu24,AdHu26, AdHu34, AdHu35, AdHu36, AdHu37, AdHu41, AdHu48, AdHu49, AdHu50,AdC6, AdC7, AdC69, bovine Ad type 3, canine Ad type 2, ovine Ad, orporcine Ad type 3. In some embodiments, the adenovirus particlecomprises an adenovirus serotype 2 capsid or a variant of an adenoviralserotype 5 capsid. In some embodiments, the viral particle is alentiviral particle encapsidating the recombinant lentiviral vector. Insome embodiments, the lentiviral particle comprises a capsid pseudotypedwith vesicular stomatitis virus (VSV), lymphocytic choriomeningitisvirus (LCMV), Ross river virus (RRV), Ebola virus, Marburg virus, Mokalavirus, Rabies virus, RD114 or variants therein. In some embodiments, theviral particle is a HSV particle. In some embodiments, the HSV particleis a rHSV-1 particle or a rHSV-2 particle.

In some embodiments, the invention provides a recombinant AAV particlecomprising any of the rAAV vectors described herein. In someembodiments, the AAV viral particle comprises an AAV1, AAV2, AAV3, AAV4,AAV5, AAV6, AAV7, AAV8, AAVrh8, AAVrh8R, AAV9, AAV10, AAVrh10, AAV11,AAV12, AAV2R471A, AAV2/2-7m8, AAV DJ, AAV2 N587A, AAV2 E548A, AAV2N708A, AAV V708K, a goat AAV, AAV1/AAV2 chimeric, bovine AAV, or mouseAAV capsid, rAAV2-HBKO capsid (see WO 2015/168666, which is incorporatedherein by reference). In some embodiments, the ITR and the capsid of therAAV viral particle are derived from the same AAV serotype. In someembodiments, the ITR and the capsid of the rAAV viral particle arederived from different AAV serotypes. In some embodiments, the ITR isderived from AAV2 and the capsid of the rAAV particle is derived fromAAV1. In some embodiments, the rAAV vector comprises 5′ to 3′ an AAV2ITR, a promoter, nucleic acid encoding the RNAi, a polyadenylationsignal, and an AAV2 ITR. In some embodiments, the promoter is a CBApromoter. In some embodiments, the polyadenylation signal is a bovinegrowth hormone polyadenylation signal. In some embodiments, the rAAVvector comprises 5′ to 3′ all or a portion (e.g., a functional portion)of an AAV2 ITR, the CBA promoter, an intron (e.g., a chimeric intron),nucleic acid encoding the RNAi, a bovine growth hormone polyadenylationsignal, and an AAV2 ITR. In some embodiments, the vector furthercomprises a stuffer nucleic acid. In some embodiments, the stuffernucleic acid further comprises nucleic acid encoding a reporterpolypeptide (e.g., green fluorescent protein (GFP)). In someembodiments, the stuffer nucleic acid is located upstream or downstreamof the nucleic acid encoding the RNAi.

In some embodiments, the invention provides a composition (e.g., apharmaceutical composition) comprising any of the viral particles (e.g.,rAAV particles) described herein. In some embodiments, the compositionfurther comprises a pharmaceutically acceptable carrier.

In some aspects, the invention provides a kit comprising any of the RNAidescribed herein. In some embodiments, the kit comprises any of theviral particles (e.g., rAAV particles) described herein. In someembodiments, the kit comprises any of the compositions described herein.In some embodiments, the kit further comprises instructions for use.

In some aspects, the invention provides methods for treatingHuntington's disease in a mammal comprising administering to the mammalan RNAi comprising a first strand comprising a first nucleic acidcomprising the sequence 5′-UGGCCGUCCAUCUUCGACCCG-3′ (SEQ ID NO: 1) and asecond strand comprising a second nucleic acid comprising the sequence5′-CGGGUCCAAGAUGGACGGCCA-3′ (SEQ ID NO:2) or a first strand comprising afirst nucleic acid comprising the sequence 5′-AGUCGGUGUGGUUGACAAGCA-3′(SEQ ID NO:7) and a second strand comprising a second nucleic acidcomprising the sequence 5′-UGCUUGUCAACCACACCGACU-3′ (SEQ ID NO:8). Insome aspects, the invention provides methods for inhibiting theexpression of htt in a mammal with Huntington's disease comprisingadministering to the mammal an RNAi comprising a first strand comprisinga first nucleic acid comprising the sequence 5′-UGGCCGUCCAUCUUGGACCCG-3′(SEQ ID NO: 1) and a second strand comprising a second nucleic acidcomprising the sequence 5′-CGGGUCCAAGAUGGACGGCCA-3′ (SEQ ID NO:2) or afirst strand comprising a first nucleic acid comprising the sequence5′-AGUCGGGUGUGGUUGACAAGCA-3′ (SEQ ID NO:7) and a second strandcomprising a second nucleic acid comprising the sequence5′-UGCUUGUCAACCACACCGACU-3′ (SEQ ID NO: 10). In some aspects, theinvention provides methods for inhibiting the accumulation of htt in acell of a mammal with Huntington's disease comprising administering tothe mammal an RNAi comprising a first strand comprising a first nucleicacid comprising the sequence 5′-UGGCCGUCCAUCUUGGACCCG-3′ (SEQ ID NO:1)and a second strand comprising a second nucleic acid comprising thesequence 5′-CGGGUCCAAGAUGGACGGCCA-3′ (SEQ ID NO:2) or a first strandcomprising a first nucleic acid comprising the sequence5′-AGUCGGUGUGGUUGACAAGCA-3′ (SEQ ID NO:7) and a second strand comprisinga second nucleic acid comprising the sequence5′-UGCUUGUCAACCACACCGACU-3′ (SEQ ID NO:8).

In some embodiments of the above methods, the first strand comprises anucleic acid sequence having about 90% identity to SEQ ID NO:1 or about90% identity to SEQ ID NO:7. In some embodiments, the second strandcomprises a nucleic acid sequence having about 90% identity to SEQ IDNO:2 or about 90% identity to SEQ ID NO:8. In some embodiments, thefirst strand and the second strand are linked by means of RNA linkercapable of forming a loop structure. In some embodiments, the RNA linkercomprises from 4 to 50 nucleotides. In some embodiments, the loopstructure comprises 4 to 20 nucleotides. In some embodiments, the RNAicomprises 5′ to 3′ the second strand, the RNA linker, and the firststrand. In some embodiments, the RNAi comprises 5′ to 3′ the firststrand, the RNA linker, and the second strand. In some embodiments, theRNAi comprises the nucleic acid sequence of SEQ ID NO:4 or SEQ ID NO:10.In some embodiments, the RNAi comprises a nucleotide sequence about 90%identical to the nucleotide sequence of SEQ ID NO:4 or SEQ ID NO: 10.

In some embodiments of the above methods, the RNAi is encoded on anexpression construct. In some embodiments, the nucleic acid encoding theRNAi comprises a miRNA scaffold. In some embodiments, the nucleic acidencoding the RNAi is operably linked to a promoter. In some embodiments,the promoter is capable of expressing the RNAi in the brain of a mammal.In some embodiments, the promoter is selected from a cytomegalovirus(CMV) immediate early promoter, a RSV LTR, a MoMLV LTR, aphosphoglycerate kinase-1 (PGK) promoter, a simian virus 40 (SV40)promoter, a CK6 promoter, a transthyretin promoter (TTR), a TK promoter,a tetracycline responsive promoter (TRE), an HBV promoter, an hAATpromoter, a LSP promoter, a chimeric liver-specific promoter (LSP), aE2F promoter, a telomerase (hTERT) promoter; a cytomegalovirusenhancer/chicken beta-actin/Rabbit β-globin (CAG) promoter, anelongation factor 1-alpha promoter (EFl-alpha) promoter and a humanβ-glucuronidase promoter. In some embodiments, the promoter is a hybridchicken β-actin promoter. In some embodiments, the nucleic acid furthercomprises all or a portion (e.g., functional portion) of an intron and apolyadenylation signal. In some embodiments, the polyadenylation signalis a bovine growth hormone polyadenylation signal, and the intron is achimeric intron.

In some embodiments of the above methods, the RNAi is encoded on avector comprising the expression construct of any one of the embodimentsdescribed herein. In some embodiments, the vector is a recombinantadeno-associated virus (rAAV) vector, a recombinant adenoviral vector, arecombinant lentiviral vector or a recombinant herpes simplex virus(HSV) vector. In some embodiments, the vector is a recombinantadenoviral vector. In some embodiments, the recombinant adenoviralvector is derived from Adenovirus serotype 2, 1, 5, 6, 19, 3, 11, 7, 14,16, 21, 12, 18, 31, 8, 9, 10, 13, 15, 17, 19, 20, 22, 23, 24-30, 37, 40,41, AdHu2, AdHu 3, AdHu4, AdHu24, AdHu26, AdHu34, AdHu35, AdHu36,AdHu37, AdHu41, AdHu48, AdHu49, AdHu50, AdC6, AdC7, AdC69, bovine Adtype 3, canine Ad type 2, ovine Ad, or porcine Ad type 3. In someembodiments, the recombinant adenoviral vector is derived fromadenovirus serotype 2 or a variant of adenoviral serotype 5. In someembodiments, the vector is a recombinant lentiviral vector. In someembodiments, the recombinant lentiviral vector is derived from alentivirus pseudotyped with vesicular stomatitis virus (VSV),lymphocytic choriomeningitis virus (LCMV), Ross river virus (RRV), Ebolavirus, Marburg virus, Mokala virus, Rabies virus, RD114 or variantstherein. In some embodiments, the vector is a rHSV vector. In someembodiments, the rHSV vector is derived from rHSV-1 or rHSV-2.

In some embodiments of the above methods, the vector is a rAAV vector.In some embodiments, the expression construct is flanked by one or moreAAV inverted terminal repeat (ITR) sequences. In some embodiments, theexpression construct is flanked by two AAV ITRs. In some embodiments,the AAV ITRs are AAV1, AAV2, AAV3, AAV4, AAV5, AAV6, AAV7, AAV8, AAVrh8,AAVrh8R, AAV9, AAV10, AAVrh10, AAV11, AAV12, AAV2R471A, AAV DJ, a goatAAV, bovine AAV, or mouse AAV serotype ITRs. In some embodiments, theAAV ITRs are AAV2 ITRs. In some embodiments, the vector furthercomprises a stuffer nucleic acid. In some embodiments, the stuffernucleic acid is located between the promoter and the nucleic acidencoding the RNAi. In some embodiments, the vector is aself-complementary rAAV vector. In some embodiments, the vectorcomprises first nucleic acid sequence encoding the RNAi and a secondnucleic acid sequence encoding a complement of the RNAi, wherein thefirst nucleic acid sequence can form intrastrand base pairs with thesecond nucleic acid sequence along most or all of its length. In someembodiments, the first nucleic acid sequence and the second nucleic acidsequence are linked by a mutated AAV ITR, wherein the mutated AAV ITRcomprises a deletion of the D region and comprises a mutation of theterminal resolution sequence. In some embodiments, the inventionprovides a cell comprising any of vectors (e.g., rAAV vectors) describedherein.

In some embodiments of the above methods, vector encoding the RNAi is ina viral particle, wherein the viral particle is an AAV particleencapsidating the rAAV vector, an adenovirus particle encapsidating therecombinant adenoviral vector, a lentiviral particle encapsidating therecombinant lentiviral vector or an HSV particle encapsidating therecombinant HSV vector. In some embodiments, the viral particle is anadenovirus particle encapsidating the recombinant adenoviral vector. Insome embodiments, the adenovirus particle comprises a capsid fromAdenovirus serotype 2, 1, 5, 6, 19, 3, 11, 7, 14, 16, 21, 12, 18, 31, 8,9, 10, 13, 15, 17, 19, 20, 22, 23, 24-30, 37, 40, 41, AdHu2, AdHu 3,AdHu4, AdHu24, AdHu26, AdHu34, AdHu35, AdHu36, AdHu37, AdHu41, AdHu48,AdHu49, AdHu50, AdC6, AdC7, AdC69, bovine Ad type 3, canine Ad type 2,ovine Ad, or porcine Ad type 3. In some embodiments, the adenovirusparticle comprises an adenovirus serotype 2 capsid or a variant of anadenoviral serotype 5 capsid. In some embodiments, the viral particle isa lentiviral particle encapsidating the recombinant lentiviral vector.In some embodiments, the lentiviral particle comprises a capsidpseudotyped with vesicular stomatitis virus (VSV), lymphocyticchoriomeningitis virus (LCMV), Ross river virus (RRV), Ebola virus,Marburg virus, Mokala virus, Rabies virus, RD114 or variants therein. Insome embodiments, the viral particle is a HSV particle. In someembodiments, the HSV particle is a rHSV-1 particle or a rHSV-2 particle.

In some embodiments of the above methods, the invention provides arecombinant AAV particle comprising any of the rAAV vectors describedherein. In some embodiments, the AAV viral particle comprises an AAV1,AAV2, AAV3, AAV4, AAV5, AAV6, AAV7, AAV8, AAVrh8, AAVrh8R, AAV9, AAV10,AAVrh10, AAV11, AAV12, AAV2R471A, AAV2/2-7m8, AAV DJ, AAV2 N587A, AAV2E548A, AAV2 N708A, AAV V708K, a goat AAV, AAV1/AAV2 chimeric, bovineAAV, or mouse AAV capsid rAAV2/HBoV1 serotype capsid. In someembodiments, the ITR and the capsid of the rAAV viral particle arederived from the same AAV serotype. In some embodiments, the ITR and thecapsid of the rAAV viral particle are derived from different AAVserotypes. In some embodiments, the ITR is derived from AAV2 and thecapsid of the rAAV particle is derived from AAV1. The invention providesa vector comprising the expression construct of any one of theembodiments described herein. In some embodiments, the vector is arecombinant adeno-associated virus (rAAV) vector, a recombinantadenoviral vector, a recombinant lentiviral vector or a recombinantherpes simplex virus (HSV) vector. In some embodiments, the vector is arecombinant adenoviral vector. In some embodiments, the recombinantadenoviral vector is derived from Adenovirus serotype 2, 1, 5, 6, 19, 3,11, 7, 14, 16, 21, 12, 18, 31, 8, 9, 10, 13, 15, 17, 19, 20, 22, 23,24-30, 37, 40, 41, AdHu2, AdHu 3, AdHu4, AdHu24, AdHu26, AdHu34, AdHu35,AdHu36, AdHu37, AdHu41, AdHu48, AdHu49, AdHu50, AdC6, AdC7, AdC69,bovine Ad type 3, canine Ad type 2, ovine Ad, or porcine Ad type 3. Insome embodiments, the recombinant adenoviral vector is derived fromadenovirus serotype 2 or a variant of adenoviral serotype 5. In someembodiments, the vector is a recombinant lentiviral vector. In someembodiments, the recombinant lentiviral vector is derived from alentivirus pseudotyped with vesicular stomatitis virus (VSV),lymphocytic choriomeningitis virus (LCMV), Ross river virus (RRV), Ebolavirus, Marburg virus, Mokala virus, Rabies virus, RD114 or variantstherein. In some embodiments, the vector is a rHSV vector. In someembodiments, the rHSV vector is derived from rHSV-1 or rHSV-2.

In some embodiments of the above aspects and embodiments, the vector isa rAAV vector. In some embodiments, the expression construct is flankedby one or more AAV inverted terminal repeat (ITR) sequences. In someembodiments, the expression construct is flanked by two AAV ITRs. Insome embodiments, the AAV ITRs are AAV1, AAV2, AAV3, AAV4, AAV5, AAV6,AAV7, AAV8, AAVrh8, AAVrh8R, AAV9, AAV10, AAVrh10, AAV11, AAV12,AAV2R471A, AAV DJ, a goat AAV, bovine AAV, or mouse AAV serotype ITRs.In some embodiments, the AAV ITRs are AAV2 ITRs. In some embodiments,the vector further comprises a stuffer nucleic acid. In someembodiments, the stuffer nucleic acid is located between the promoterand the nucleic acid encoding the RNAi. In some embodiments, the vectoris a self-complementary rAAV vector. In some embodiments, the vectorcomprises first nucleic acid sequence encoding the RNAi and a secondnucleic acid sequence encoding a complement of the RNAi, wherein thefirst nucleic acid sequence can form intrastrand base pairs with thesecond nucleic acid sequence along most or all of its length. In someembodiments, the first nucleic acid sequence and the second nucleic acidsequence are linked by a mutated AAV ITR, wherein the mutated AAV ITRcomprises a deletion of the D region and comprises a mutation of theterminal resolution sequence. In some embodiments, the inventionprovides a cell comprising any of vectors (e.g., rAAV vectors) describedherein.

In some embodiments of the above aspects and embodiments, the inventionprovides a viral particle comprising any of the vectors describedherein, wherein the viral particle is an AAV particle encapsidating therAAV vector, an adenovirus particle encapsidating the recombinantadenoviral vector, a lentiviral particle encapsidating the recombinantlentiviral vector or an HSV particle encapsidating the recombinant HSVvector. In some embodiments, the viral particle is an adenovirusparticle encapsidating the recombinant adenoviral vector. In someembodiments, the adenovirus particle comprises a capsid from Adenovirusserotype 2, 1, 5, 6, 19, 3, 11, 7, 14, 16, 21, 12, 18, 31, 8, 9, 10, 13,15, 17, 19, 20, 22, 23, 24-30, 37, 40, 41, AdHu2, AdHu 3, AdHu4, AdHu24,AdHu26, AdHu34, AdHu35, AdHu36, AdHu37, AdHu41, AdHu48, AdHu49, AdHu50,AdC6, AdC7, AdC69, bovine Ad type 3, canine Ad type 2, ovine Ad, orporcine Ad type 3. In some embodiments, the adenovirus particlecomprises an adenovirus serotype 2 capsid or a variant of an adenoviralserotype 5 capsid. In some embodiments, the viral particle is alentiviral particle encapsidating the recombinant lentiviral vector. Insome embodiments, the lentiviral particle comprises a capsid pseudotypedwith vesicular stomatitis virus (VSV), lymphocytic choriomeningitisvirus (LCMV), Ross river virus (RRV), Ebola virus, Marburg virus, Mokalavirus, Rabies virus, RD114 or variants therein. In some embodiments, theviral particle is a HSV particle. In some embodiments, the HSV particleis a rHSV-1 particle or a rHSV-2 particle.

In some embodiments, the invention provides a recombinant AAV particlecomprising any of the rAAV vectors described herein. In someembodiments, the AAV viral particle comprises an AAV1, AAV2, AAV3, AAV4,AAV5, AAV6, AAV7, AAV8, AAVrh8, AAVrh8R, AAV9, AAV10, AAVrh10, AAV11,AAV12, AAV2R471A, AAV2/2-7m8, AAV DJ, AAV2 N587A, AAV2 E548A, AAV2N708A, AAV V708K, a goat AAV, AAV1/AAV2 chimeric, bovine AAV, or mouseAAV capsid rAAV2/HBoV1 serotype capsid. In some embodiments, the ITR andthe capsid of the rAAV viral particle are derived from the same AAVserotype. In some embodiments, the ITR and the capsid of the rAAV viralparticle are derived from different AAV serotypes. In some embodiments,the ITR is derived from AAV2 and the capsid of the rAAV particle isderived from AAV1. In some embodiments, the rAAV vector comprises 5′ to3′ an AAV2 ITR, a promoter, nucleic acid encoding the RNAi, apolyadenylation signal, and an AAV2 ITR. In some embodiments, thepromoter is a CBA promoter. In some embodiments, the polyadenylationsignal is a bovine growth hormone polyadenylation signal. In someembodiments, the rAAV vector comprises 5′ to 3′ an AAV2 ITR, the CBApromoter, an intron, nucleic acid encoding the RNAi, a bovine growthhormone polyadenylation signal, and an AAV2 ITR. In some embodiments,the vector further comprises a stuffer nucleic acid. In someembodiments, the stuffer nucleic acid comprises nucleic acid encoding agreen fluorescent protein (GFP). In some embodiments, the stuffernucleic acid is located between the promoter and the nucleic acidencoding the RNAi.

In some embodiments of the above methods, the viral particle (e.g., therAAV particle) is in a composition (e.g., a pharmaceutical composition).In some embodiments, the composition further comprises apharmaceutically acceptable carrier.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A shows a DNA sequence for Htt miRNA 206 (SEQ ID NO:22) and HttmiRNA 207 (SEQ ID NO:9). FIG. 1B shows a map of ssAAV2/1miRHtt.de. FIG.1C shows the sequence of the coding strand of ssAAV2/1miRHtt.de (SEQ IDNO: 16) and the noncoding strand of ssAAV2/1miRHtt.de (SEQ ID NO:19).

FIG. 2 shows the ability of Htt miRNA 170XA, Htt miRNA 206 and Htt miRNA207 to mediate Htt reduction in vitro. Values are given as themeans±SEM.

FIGS. 3A and 3B show the ability of AAV2/1-Htt miRNA 206 and AAV2/1-HttmiRNA 207 to mediate Htt reduction as measured by protein (FIG. 3A) ormRNA (FIG. 3B). CTL-3 is a noncoding miRNA control. Values are given asthe means±SEM. * indicates significantly different from CTL3 mice,p<0.05; ANOVA followed by Tukey's post-hoc test.

FIGS. 4A and 4B show body weight (FIG. 4A) and brain weight (FIG. 4B)one month after administration of AAV2/1-Htt miRNA 206 and AAV2/1-HttmiRNA 207. CTL-3 is a noncoding miRNA control. *Significantly differentfrom CTL3 control mice, p<0.05; ANOVA followed by Tukey's post-hoc test.

FIGS. 5A-5D show human Htt was significantly reduced in the striatum ofAAV2/1-miRNA-Htt-207 injected YAC128 and FVB wild-type littermate mice.Human HTT protein levels are shown in FIG. 5A. Mouse HTT protein levelsare shown in FIG. 5B. Human HTT mRNA levels are shown in FIG. 5C. MouseHTT mRNA levels are shown in FIG. 5D.

FIGS. 6A and 6B show that treatment with AAV2/1-miRNA-Htt-207 cancorrect motor coordination deficits in YAC128 mice as determined byrotarod test (FIG. 6A) and a depressive phenotype in YAC128 mice asdetermined using the Porsolt swim test (FIG. 6B). Mice were either wildtype (WT also referred to as FVB) or YAC128 (YAC) treated with anon-coding RNA control (CTL3) or AAV2/1-miRNA-Htt-207 (207). FIG. 6 *indicate a significant deficiency in CTL3 noncoding miRNA control mice,p<0.05; ANOVA followed by Tukey's post-hoc test compared to wild typemice, wild type mice treated with AAV2/1-miRNA-Htt-207, and YAC128 micetreated with AAV2/1-miRNA-Htt-207.

FIGS. 7A and 7B show body weights (FIG. 7A) and brain weights (FIG. 7B)three months post infection. Mice were either wild type (WT) or YAC128(YAC) treated with a non-coding RNA control (CTL3) orAAV2/1-miRNA-Htt-207 (207).

FIG. 8 shows a map of a self-complementary miRHtt 207 vector genome. CMVenh/CBA promoter is the CMV enhancer/chicken beta actin promoter. Δchimeric intron is an abbreviated chimeric intron. BGH is the bovinegrowth hormone polyadenylation signal. ΔITR is an AAV ITR lacking theterminal resolution sequence.

FIG. 9 shows a map of an alternative self-complementary miRHtt 207vector genome. CBA promoter is the chicken beta actin promoter. Δchimeric intron is an abbreviated chimeric intron. BGH is the bovinegrowth hormone polyadenylation signal.

DETAILED DESCRIPTION

In some aspects, the invention provides RNAi for treating Huntington'sdisease, wherein the RNAi comprises a first strand comprising a firstnucleic acid comprising the sequence 5′-UGGCCGUCCAUCUUGGACCCG-3′ (SEQ IDNO: 1) and a second strand comprising a second nucleic acid comprisingthe sequence 5′-CGGGUCCAAGAUGGACGGCCA-3′ (SEQ ID NO:2), where the firststrand and second strand form a duplex. In some aspects, the inventionprovides RNAi for treating Huntington's disease, wherein the RNAicomprises a first strand comprising a first nucleic acid comprising thesequence 5′-AGUCGGUGUGGUUGACAAGCA-3′ (SEQ ID NO:7) and a second strandcomprising a second nucleic acid comprising the sequence5′-UGCUUGUCAACCACACCGACU-3′ (SEQ ID NO:8), where the first strand andsecond strand form a duplex. In some aspects, the invention providesexpression cassettes, vectors (e.g., recombinant AAV, adenoviral,lentiviral, or HSV vectors), cells, viral particles (e.g., AAV,adenoviral, lentiviral, or HSV viral particles), and pharmaceuticalcompositions comprising an RNAi of the present disclosure. In furtheraspects, the invention provides methods for treating Huntington'sdisease, inhibiting the expression of htt, and inhibiting theaccumulation of htt in a cell in a mammal comprising administering tothe mammal a pharmaceutical composition comprising an RNAi of thepresent disclosure. In still further aspects, the invention provides forthe use of a pharmaceutical composition comprising an RNAi of thepresent disclosure to treat Huntington's disease (e.g., ameliorate thesymptoms of Huntington's disease), inhibit the expression of htt, orinhibit the accumulation of htt in a cell in a mammal with Huntington'sdisease. In yet further aspects, the invention provides kits fortreating Huntington's disease in a mammal comprising an RNAi of thepresent disclosure.

I. General Techniques

The techniques and procedures described or referenced herein aregenerally well understood and commonly employed using conventionalmethodology by those skilled in the art, such as, for example, thewidely utilized methodologies described in Molecular Cloning: ALaboratory Manual (Sambrook et al., 4^(th) ed., Cold Spring HarborLaboratory Press, Cold Spring Harbor, N.Y., 2012); Current Protocols inMolecular Biology (F. M. Ausubel, et al. eds., 2003); the series Methodsin Enzymology (Academic Press, Inc.); PCR 2: A Practical Approach (M. J.MacPherson, B. D. Hames and G. R. Taylor eds., 1995); Antibodies, ALaboratory Manual (Harlow and Lane, eds., 1988); Culture of AnimalCells: A Manual of Basic Technique and Specialized Applications (R. I.Freshney, 6^(th) ed., J. Wiley and Sons, 2010); OligonucleotideSynthesis (M. J. Gait, ed., 1984); Methods in Molecular Biology, HumanaPress; Cell Biology: A Laboratory Notebook (J. E. Cellis, ed., AcademicPress, 1998); Introduction to Cell and Tissue Culture (J. P. Mather andP. E. Roberts, Plenum Press, 1998); Cell and Tissue Culture: LaboratoryProcedures (A. Doyle, J. B. Griffiths, and D. G. Newell, eds., J. Wileyand Sons, 1993-8); Handbook of Experimental Immunology (D. M. Weir andC. C. Blackwell, eds., 1996); Gene Transfer Vectors for Mammalian Cells(J. M. Miller and M. P. Calos, eds., 1987); PCR: The Polymerase ChainReaction, (Mullis et al., eds., 1994); Current Protocols in Immunology(J. E. Coligan et al., eds., 1991); Short Protocols in Molecular Biology(Ausubel et al., eds., J. Wiley and Sons, 2002); Immunobiology (C. A.Janeway et al., 2004); Antibodies (P. Finch, 1997): Antibodies: APractical Approach (D. Catty, ed., IRL Press, 1988-1989); MonoclonalAntibodies: A Practical Approach (P. Shepherd and C. Dean, eds., OxfordUniversity Press, 2000); Using Antibodies: A Laboratory Manual (E.Harlow and D. Lane, Cold Spring Harbor Laboratory Press, 1999); TheAntibodies (M. Zanetti and J. D. Capra, eds., Harwood AcademicPublishers, 1995); and Cancer: Principles and Practice of Oncology (V.T. DeVita et al., eds., J. B. Lippincott Company, 2011).

II. Definitions

A “vector.” as used herein, refers to a recombinant plasmid or virusthat comprises a nucleic acid to be delivered into a host cell, eitherin vitro or in vivo.

The term “polynucleotide” or “nucleic acid” as used herein refers to apolymeric form of nucleotides of any length, either ribonucleotides ordeoxyribonucleotides. Thus, this term includes, but is not limited to,single-, double- or multi-stranded DNA or RNA, genomic DNA, cDNA,DNA-RNA hybrids, or a polymer comprising purine and pyrimidine bases, orother natural, chemically or biochemically modified, non-natural, orderivatized nucleotide bases. The backbone of the polynucleotide cancomprise sugars and phosphate groups (as may typically be found in RNAor DNA), or modified or substituted sugar or phosphate groups.Alternatively, the backbone of the polynucleotide can comprise a polymerof synthetic subunits such as phosphoramidates and thus can be anoligodeoxynucleoside phosphoramidate (P—NH₂) or a mixedphosphoramidate-phosphodiester oligomer. In addition, a double-strandedpolynucleotide can be obtained from the single stranded polynucleotideproduct of chemical synthesis either by synthesizing the complementarystrand and annealing the strands under appropriate conditions, or bysynthesizing the complementary strand de novo using a DNA polymerasewith an appropriate primer.

The terms “polypeptide” and “protein” are used interchangeably to referto a polymer of amino acid residues, and are not limited to a minimumlength. Such polymers of amino acid residues may contain natural ornon-natural amino acid residues, and include, but are not limited to,peptides, oligopeptides, dimers, trimers, and multimers of amino acidresidues. Both full-length proteins and fragments thereof areencompassed by the definition. The terms also include post-expressionmodifications of the polypeptide, for example, glycosylation,sialylation, acetylation, phosphorylation, and the like. Furthermore,for purposes of the present invention, a “polypeptide” refers to aprotein which includes modifications, such as deletions, additions, andsubstitutions (generally conservative in nature), to the nativesequence, as long as the protein maintains the desired activity. Thesemodifications may be deliberate, as through site-directed mutagenesis,or may be accidental, such as through mutations of hosts which producethe proteins or errors due to PCR amplification.

A “recombinant viral vector” refers to a recombinant polynucleotidevector comprising one or more heterologous sequences (i.e., nucleic acidsequence not of viral origin). In the case of recombinant AAV vectors,the recombinant nucleic acid is flanked by at least one, and in someembodiments two, inverted terminal repeat sequences (ITRs).

A “recombinant AAV vector (rAAV vector)” refers to a polynucleotidevector comprising one or more heterologous sequences (i.e., nucleic acidsequence not of AAV origin) that are flanked by at least one, and insome embodiments two, AAV inverted terminal repeat sequences (ITRs).Such rAAV vectors can be replicated and packaged into infectious viralparticles when present in a host cell that has been infected with asuitable helper virus (or that is expressing suitable helper functions)and that is expressing AAV rep and cap gene products (i.e. AAV Rep andCap proteins). When a rAAV vector is incorporated into a largerpolynucleotide (e.g., in a chromosome or in another vector such as aplasmid used for cloning or transfection), then the rAAV vector may bereferred to as a “pro-vector” which can be “rescued” by replication andencapsidation in the presence of AAV packaging functions and suitablehelper functions. A rAAV vector can be in any of a number of forms,including, but not limited to, plasmids, linear artificial chromosomes,complexed with lipids, encapsulated within liposomes, and encapsidatedin a viral particle, particularly an AAV particle. A rAAV vector can bepackaged into an AAV virus capsid to generate a “recombinantadeno-associated viral particle (rAAV particle)”.

A “recombinant adenoviral vector” refers to a polynucleotide vectorcomprising one or more heterologous sequences (i.e., nucleic acidsequence not of adenovirus origin) that are flanked by at least oneadenovirus inverted terminal repeat sequence (ITR). In some embodiments,the recombinant nucleic acid is flanked by two inverted terminal repeatsequences (ITRs). Such recombinant viral vectors can be replicated andpackaged into infectious viral particles when present in a host cellthat is expressing essential adenovirus genes deleted from therecombinant viral genome (e.g., E1 genes, E2 genes, E4 genes, etc.).When a recombinant viral vector is incorporated into a largerpolynucleotide (e.g., in a chromosome or in another vector such as aplasmid used for cloning or transfection), then the recombinant viralvector may be referred to as a “pro-vector” which can be “rescued” byreplication and encapsidation in the presence of adenovirus packagingfunctions. A recombinant viral vector can be in any of a number offorms, including, but not limited to, plasmids, linear artificialchromosomes, complexed with lipids, encapsulated within liposomes, andencapsidated in a viral particle, for example, an adenovirus particle. Arecombinant viral vector can be packaged into an adenovirus virus capsidto generate a “recombinant adenoviral particle.”

A “recombinant lentivirus vector” refers to a polynucleotide vectorcomprising one or more heterologous sequences (i.e., nucleic acidsequence not of lentivirus origin) that are flanked by at least onelentivirus terminal repeat sequences (LTRs). In some embodiments, therecombinant nucleic acid is flanked by two lentiviral terminal repeatsequences (LTRs). Such recombinant viral vectors can be replicated andpackaged into infectious viral particles when present in a host cellthat has been infected with a suitable helper functions. A recombinantlentiviral vector can be packaged into a lentivirus capsid to generate a“recombinant lentiviral particle.”

A “recombinant herpes simplex vector (recombinant HSV vector)” refers toa polynucleotide vector comprising one or more heterologous sequences(i.e., nucleic acid sequence not of HSV origin) that are flanked by HSVterminal repeat sequences. Such recombinant viral vectors can bereplicated and packaged into infectious viral particles when present ina host cell that has been infected with a suitable helper functions.When a recombinant viral vector is incorporated into a largerpolynucleotide (e.g., in a chromosome or in another vector such as aplasmid used for cloning or transfection), then the recombinant viralvector may be referred to as a “pro-vector” which can be “rescued” byreplication and encapsidation in the presence of HSV packagingfunctions. A recombinant viral vector can be in any of a number offorms, including, but not limited to, plasmids, linear artificialchromosomes, complexed with lipids, encapsulated within liposomes, andencapsidated in a viral particle, for example, an HSV particle. Arecombinant viral vector can be packaged into an HSV capsid to generatea “recombinant herpes simplex viral particle.”

“Heterologous” means derived from a genotypically distinct entity fromthat of the rest of the entity to which it is compared or into which itis introduced or incorporated. For example, a polynucleotide introducedby genetic engineering techniques into a different cell type is aheterologous polynucleotide (and, when expressed, can encode aheterologous polypeptide). Similarly, a cellular sequence (e.g., a geneor portion thereof) that is incorporated into a viral vector is aheterologous nucleotide sequence with respect to the vector.

The term “transgene” refers to a polynucleotide that is introduced intoa cell and is capable of being transcribed into RNA and optionally,translated and/or expressed under appropriate conditions. In aspects, itconfers a desired property to a cell into which it was introduced, orotherwise leads to a desired therapeutic or diagnostic outcome. Inanother aspect, it may be transcribed into a molecule that mediates RNAinterference, such as miRNA, siRNA, or shRNA.

“Chicken β-actin (CBA) promoter” refers to a polynucleotide sequencederived from a chicken β-actin gene (e.g., Gallus gallus beta actin,represented by GenBank Entrez Gene ID 396526). As used herein, “chickenβ-actin promoter” may refer to a promoter containing a cytomegalovirus(CMV) early enhancer element, the promoter and first exon and intron ofthe chicken β-actin gene, and the splice acceptor of the rabbitbeta-globin gene, such as the sequences described in Miyazaki, J. et al.(1989) Gene 79(2):269-77. As used herein, the term “CAG promoter” may beused interchangeably. As used herein, the term “CMV earlyenhancer/chicken beta actin (CAG) promoter” may be used interchangeably.

The terms “genome particles (gp),” “genome equivalents,” or “genomecopies” as used in reference to a viral titer, refer to the number ofvirions containing the recombinant AAV DNA genome, regardless ofinfectivity or functionality. The number of genome particles in aparticular vector preparation can be measured by procedures such asdescribed in the Examples herein, or for example, in Clark et al. (1999)Hum. Gene Ther., 10:1031-1039; Veldwijk et al. (2002) Mol. Ther.,6:272-278.

The term “vector genome (vg)” as used herein may refer to one or morepolynucleotides comprising a set of the polynucleotide sequences of avector, e.g., a viral vector. A vector genome may be encapsidated in aviral particle. Depending on the particular viral vector, a vectorgenome may comprise single-stranded DNA, double-stranded DNA, orsingle-stranded RNA, or double-stranded RNA. A vector genome may includeendogenous sequences associated with a particular viral vector and/orany heterologous sequences inserted into a particular viral vectorthrough recombinant techniques. For example, a recombinant AAV vectorgenome may include at least one ITR sequence flanking a promoter, astuffer, a sequence of interest (e.g., an RNAi), and a polyadenylationsequence. A complete vector genome may include a complete set of thepolynucleotide sequences of a vector. In some embodiments, the nucleicacid titer of a viral vector may be measured in terms of vg/mL. Methodssuitable for measuring this titer are known in the art (e.g.,quantitative PCR).

As used herein, the term “inhibit” may refer to the act of blocking,reducing, eliminating, or otherwise antagonizing the presence, or anactivity of, a particular target. Inhibition may refer to partialinhibition or complete inhibition. For example, inhibiting theexpression of a gene may refer to any act leading to a blockade,reduction, elimination, or any other antagonism of expression of thegene, including reduction of mRNA abundance (e.g., silencing mRNAtranscription), degradation of mRNA, inhibition of mRNA translation, andso forth. In some embodiments, inhibiting the expression of HTT mayrefer a blockade, reduction, elimination, or any other antagonism ofexpression of HTT, including reduction of HTT mRNA abundance (e.g.,silencing HTT mRNA transcription), degradation of HTT mRNA, inhibitionof HTT mRNA translation, and so forth. As another example, inhibitingthe accumulation of a protein in a cell may refer to any act leading toa blockade, reduction, elimination, or other antagonism of expression ofthe protein, including reduction of mRNA abundance (e.g., silencing mRNAtranscription), degradation of mRNA, inhibition of mRNA translation,degradation of the protein, and so forth. In some embodiments,inhibiting the accumulation of HTT protein in a cell refers to ablockade, reduction, elimination, or other antagonism of expression ofthe HTT protein in a cell, including reduction of HTT mRNA abundance(e.g., silencing HTT mRNA transcription), degradation of HTT mRNA,inhibition of HTT mRNA translation, degradation of the HTT protein, andso forth

The terms “infection unit (iu),” “infectious particle,” or “replicationunit,” as used in reference to a viral titer, refer to the number ofinfectious and replication-competent recombinant AAV vector particles asmeasured by the infectious center assay, also known as replicationcenter assay, as described, for example, in McLaughlin et al. (1988) J.Virol., 62:1963-1973.

The term “transducing unit (tu)” as used in reference to a viral titer,refers to the number of infectious recombinant AAV vector particles thatresult in the production of a functional transgene product as measuredin functional assays such as described in Examples herein, or forexample, in Xiao et al. (1997) Exp. Neurobiol., 144:113-124; or inFisher et al. (1996) J. Virol., 70:520-532 (LFU assay).

An “inverted terminal repeat” or “ITR” sequence is a term wellunderstood in the art and refers to relatively short sequences found atthe termini of viral genomes which are in opposite orientation.

An “AAV inverted terminal repeat (ITR)” sequence, a term well-understoodin the art, is an approximately 145-nucleotide sequence that is presentat both termini of the native single-stranded AAV genome. The outermost125 nucleotides of the ITR can be present in either of two alternativeorientations, leading to heterogeneity between different AAV genomes andbetween the two ends of a single AAV genome. The outermost 125nucleotides also contains several shorter regions ofself-complementarity (designated A, A′, B, B′, C, C′ and D regions),allowing intrastrand base-pairing to occur within this portion of theITR.

A “terminal resolution sequence” or “trs” is a sequence in the D regionof the AAV ITR that is cleaved by AAV rep proteins during viral DNAreplication. A mutant terminal resolution sequence is refractory tocleavage by AAV rep proteins.

“AAV helper functions” refer to functions that allow AAV to bereplicated and packaged by a host cell. AAV helper functions can beprovided in any of a number of forms, including, but not limited to,helper virus or helper virus genes which aid in AAV replication andpackaging. Other AAV helper functions are known in the art such asgenotoxic agents.

A “helper virus” for AAV refers to a virus that allows AAV (which is adefective parvovirus) to be replicated and packaged by a host cell. Ahelper virus provides “helper functions” which allow for the replicationof AAV. A number of such helper viruses have been identified, includingadenoviruses, herpesviruses and, poxviruses such as vaccinia andbaculovirus. The adenoviruses encompass a number of different subgroups,although Adenovirus type 5 of subgroup C (Ad5) is most commonly used.Numerous adenoviruses of human, non-human mammalian and avian origin areknown and are available from depositories such as the ATCC. Viruses ofthe herpes family, which are also available from depositories such asATCC, include, for example, herpes simplex viruses (HSV), Epstein-Barrviruses (EBV), cytomegaloviruses (CMV) and pseudorabies viruses (PRV).Examples of adenovirus helper functions for the replication of AAVinclude ElA functions, EIB functions, E2A functions, VA functions andE4orf6 functions. Baculoviruses available from depositories includeAutographa californica nuclear polyhedrosis virus.

A preparation of rAAV is said to be “substantially free” of helper virusif the ratio of infectious AAV particles to infectious helper virusparticles is at least about 10²:1; at least about 10⁴:1, at least about10⁶:1; or at least about 10⁸:1 or more. In some embodiments,preparations are also free of equivalent amounts of helper virusproteins (i.e., proteins as would be present as a result of such a levelof helper virus if the helper virus particle impurities noted above werepresent in disrupted form). Viral and/or cellular protein contaminationcan generally be observed as the presence of Coomassie staining bands onSDS gels (e.g., the appearance of bands other than those correspondingto the AAV capsid proteins VP1, VP2 and VP3).

“Percent (%) sequence identity” with respect to a reference polypeptideor nucleic acid sequence is defined as the percentage of amino acidresidues or nucleotides in a candidate sequence that are identical withthe amino acid residues or nucleotides in the reference polypeptide ornucleic acid sequence, after aligning the sequences and introducinggaps, if necessary, to achieve the maximum percent sequence identity,and not considering any conservative substitutions as part of thesequence identity. Alignment for purposes of determining percent aminoacid or nucleic acid sequence identity can be achieved in various waysthat are within the skill in the art, for instance, using publiclyavailable computer software programs, for example, those described inCurrent Protocols in Molecular Biology (Ausubel et al., eds., 1987),Supp. 30, section 7.7.18, Table 7.7.1, and including BLAST, BLAST-2,ALIGN or Megalign (DNASTAR) software. A preferred alignment program isALIGN Plus (Scientific and Educational Software, Pennsylvania). Thoseskilled in the art can determine appropriate parameters for measuringalignment, including any algorithms needed to achieve maximal alignmentover the full length of the sequences being compared. For purposesherein, the % amino acid sequence identity of a given amino acidsequence A to, with, or against a given amino acid sequence B (which canalternatively be phrased as a given amino acid sequence A that has orcomprises a certain % amino acid sequence identity to, with, or againsta given amino acid sequence B) is calculated as follows: 100 times thefraction X/Y, where X is the number of amino acid residues scored asidentical matches by the sequence alignment program in that program'salignment of A and B, and where Y is the total number of amino acidresidues in B. It will be appreciated that where the length of aminoacid sequence A is not equal to the length of amino acid sequence B, the% amino acid sequence identity of A to B will not equal the % amino acidsequence identity of B to A. For purposes herein, the % nucleic acidsequence identity of a given nucleic acid sequence C to, with, oragainst a given nucleic acid sequence D (which can alternatively bephrased as a given nucleic acid sequence C that has or comprises acertain % nucleic acid sequence identity to, with, or against a givennucleic acid sequence D) is calculated as follows: 100 times thefraction W/Z, where W is the number of nucleotides scored as identicalmatches by the sequence alignment program in that program's alignment ofC and D. and where Z is the total number of nucleotides in D. It will beappreciated that where the length of nucleic acid sequence C is notequal to the length of nucleic acid sequence D, the % nucleic acidsequence identity of C to D will not equal the % nucleic acid sequenceidentity of D to C.

An “isolated” molecule (e.g., nucleic acid or protein) or cell means ithas been identified and separated and/or recovered from a component ofits natural environment.

An “effective amount” is an amount sufficient to effect beneficial ordesired results, including clinical results (e.g., amelioration ofsymptoms, achievement of clinical endpoints, and the like). An effectiveamount can be administered in one or more administrations. In terms of adisease state, an effective amount is an amount sufficient toameliorate, stabilize, or delay development of a disease.

An “individual” or “subject” is a mammal. Mammals include, but are notlimited to, domesticated animals (e.g., cows, sheep, cats, dogs, andhorses), primates (e.g., humans and non-human primates such as monkeys),rabbits, and rodents (e.g., mice and rats). In certain embodiments, theindividual or subject is a human.

As used herein, “treatment” is an approach for obtaining beneficial ordesired clinical results. For purposes of this invention, beneficial ordesired clinical results include, but are not limited to, alleviation ofsymptoms, diminishment of extent of disease, stabilized (e.g., notworsening) state of disease, preventing spread (e.g., metastasis) ofdisease, delay or slowing of disease progression, amelioration orpalliation of the disease state, and remission (whether partial ortotal), whether detectable or undetectable. “Treatment” can also meanprolonging survival as compared to expected survival if not receivingtreatment.

As used herein, the term “prophylactic treatment” refers to treatment,wherein an individual is known or suspected to have or be at risk forhaving a disorder but has displayed no symptoms or minimal symptoms ofthe disorder. An individual undergoing prophylactic treatment may betreated prior to onset of symptoms.

“Huntington's disease (HD)” refers to the progressive brain disordertypically caused by mutations in the HTT gene (aka huntingtin, HD orIT15). It may be characterized by symptoms including abnormal movements(termed chorea), gradual loss of motor function, emotional orpsychiatric illnesses, and progressively impaired cognition. Althoughmost symptoms appear in the 30s and 40s, juvenile forms of the diseasehave also been observed. For further description of HD, see OMIM EntryNo. 143100.

“Huntingtin (HTI)” may refer either to the gene or to a polypeptideproduct thereof associated with most cases of Huntington's disease. Thenormal function of huntingtin is not fully understood. However,mutations in the huntingtin gene are known to cause HD. These mutationsare typically inherited in an autosomal dominant fashion and involveexpansion of trinucleotide CAG repeats in the HTT gene, leading to apolyglutamine (polyQ) tract in the Htt protein.

As used herein, an “RNAi” may refer to any RNA molecule that induces RNAinterference in a cell. Examples of RNAi include without limitationsmall inhibitory RNAs (siRNAs), microRNAs (miRNAs), and small hairpinRNAs (shRNAs).

“miRNA scaffold” may refer to a polynucleotide containing (i) adouble-stranded sequence targeting a gene of interest for knockdown byRNAi and (ii) additional sequences that form a stem-loop structureresembling that of endogenous miRNAs. A sequence targeting a gene ofinterest for RNAi (e.g., a short, ˜20-nt sequence) may be ligated tosequences that create a miRNA-like stem-loop and a sequence that basepairs with the sequence of interest to form a duplex when thepolynucleotide is assembled into the miRNA-like secondary structure. Asdescribed herein, this duplex may hybridize imperfectly, e.g., it maycontain one or more unpaired or mispaired bases. Upon cleavage of thispolynucleotide by Dicer, this duplex containing the sequence targeting agene of interest may be unwound and incorporated into the RISC complex.A miRNA scaffold may refer to the miRNA itself or to a DNApolynucleotide encoding the miRNA. An example of a miRNA scaffold is themiR-155 sequence (Lagos-Quintana, M. et al. (2002) Curr. Biol.12:735-9). Commercially available kits for cloning a sequence into amiRNA scaffold are known in the art (e.g., the Invitrogen™ BLOCK-iT™ PolII miR RNAi expression vector kit from Life Technologies, Thermo FisherScientific; Waltham, Mass.).

As used herein, a “bulge” refers to a region of nucleic acid that isnon-complementary to nucleic acid opposite it in a duplex nucleic acid.For example, a bulge may refer to a nucleic acid sequence that isnoncomplementary to nucleic acid opposite in a duplex nucleic acid wherethe bulge is flanked by regions of nucleic acid that are complementaryto nucleic acid opposite in a duplex nucleic acid. In some examples, thebulge may be any of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or greater than 10bases in length. In some examples, the bulge may be the result ofmispairing (e.g., the opposite strand contains a base that isnoncomplementary) or the bulge may be the result of nonpairing (e.g.,the opposite strand comprises nucleic acid complementary to nucleic acidflanking the bulge but the opposite strand does not contain nucleic acidopposite the bulge).

As used herein, the term “sense” nucleic acid is a nucleic acidcomprising a sequence that encodes all or a part of a transgene. In someexamples, mRNA for a transgene is a sense nucleic acid.

As used herein, “antisense” nucleic acid is a sequence of nucleic acidthat is complementary to a “sense” nucleic acid. For example, anantisense nucleic acid may be complementary to a mRNA encoding atransgene.

As used herein, the “guide region” of an RNAi is the strand of the RNAithat binds the target mRNA, typically on the basis of complementarity.The region of complementarity may encompass the all or a portion of theguide region. Typically, the region of complementarity includes at leastthe seed region. In many cases, the antisense region of a RNAi is theguide region.

As used herein, the “passenger region,” or “non-guide region,” usedinterchangeably herein, of an RNAi is the region of the RNAi that iscomplementary to the guide region. In many cases, the sense region of aRNAi is the passenger region.

As used herein, the “seed region” of a RNAi (e.g., miRNA) is a region ofabout 1-8 nucleotides in length of a microRNA. In some examples, theseed region and the 3′-UTR of its target mRNA may be a key determinantin RNAi recognition.

As used herein, “off-target gene silencing” refers to the pairing of aseed region of an RNAi with sequences in 3′-UTRs of unintended mRNAs anddirects translational repression and destabilization of thosetranscripts (e.g., reduces expression of the unintended mRNAs).

Reference to “about” a value or parameter herein includes (anddescribes) embodiments that are directed to that value or parameter perse. For example, description referring to “about X” includes descriptionof “X.”

As used herein, the singular form of the articles “a.” “an,” and “the”includes plural references unless indicated otherwise.

It is understood that aspects and embodiments of the invention describedherein include “comprising.” “consisting,” and/or “consistingessentially of” aspects and embodiments.

III. RNAi

In some aspects, the invention provides improved RNAi targeting htt RNAfor the treatment of Huntington's disease. In some embodiments, the RNAiis a small inhibitory RNA (siRNA), a microRNA (miRNA), or a smallhairpin RNA (shRNA). A small inhibitory or interfering RNA (siRNA) isknown in the art as a double-stranded RNA molecule of approximately19-25 (e.g., 19-23) base pairs in length that induces RNAi in a cell. Asmall hairpin RNA (shRNA) is known in the art as an RNA moleculecomprising approximately 19-25 (e.g., 19-23) base pairs of doublestranded RNA linked by a short loop (e.g., ˜4-11 nucleotides) thatinduces RNAi in a cell. In some embodiments, the RNAi comprises a firststrand and a second strand, wherein a) the first strand and the secondstrand form a duplex; b) the first strand comprises a guide region,wherein the guide region comprises the nucleic acid sequence5′-UGGCCGUCCAUCUUGGACCCG-3′ (SEQ ID NO:1) or 5′-AGUCGGUGUGGUUGACAAGCA-3′(SEQ ID NO:7); and c) the second strand comprises a non-guide region. Insome embodiments, the nucleic the guide region comprises the nucleicacid sequence 5′-UGGCCGUCCAUCUUGGACCCG-3′ (SEQ ID NO: 1) and thenon-guide region comprises the sequence 5′-CGGGUCCAAGAUGGACGGCCA-3′ (SEQID NO:2). In other embodiments, the nucleic the guide region comprisesthe nucleic acid sequence 5′-AGUCGGUGUGGUUGACAAGCA-3′ (SEQ ID NO:7) andthe non-guide region comprises the sequence 5′-UGCUUGUCAACCACACCGACU-3′(SEQ ID NO:8).

In some embodiments, the first strand comprises a guide region, whereinthe guide region comprises a nucleic acid sequence having more thanabout 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99% identity to5′-UGGCCGUCCAUCUUGGACCCG-3′ (SEQ ID NO:1). In some embodiments, thefirst strand comprises a guide region, wherein the guide regioncomprises a nucleic acid sequence having more than about 75%, 80%, 85%,90%, 95%, 96%, 97%, 98%, 99% identity to 5′-UGGCCGUCCAUCUUGGACCCG-3′(SEQ ID NO:1) but maintains at least one CpG motif. In some embodiments,the first strand comprises a guide region, wherein the guide regioncomprises a nucleic acid sequence having more than about 75%, 80%, 85%,90%, 95%, 96%, 97%, 98%, 99% identity to 5′-AGUCGGUGUGGUUGACAAGCA-3′(SEQ ID NO:7). In some embodiments, the first strand comprises a guideregion, wherein the guide region comprises a nucleic acid sequencehaving more than about 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%identity to 5′-AGUCGGUGUGGUUGACAAGCA-3′ (SEQ ID NO:7) but maintains atleast one CpG motif. In some embodiments, the second strand comprises anon-guide region, wherein the non-guide region comprises a nucleic acidsequence having more than about 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%,99% identity to 5′-CGGGUCCAAGAUGGACGGCCA-3′ (SEQ ID NO:2). In someembodiments, the second strand comprises a non-guide region, wherein thenon-guide region comprises a nucleic acid sequence having more thanabout 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99% identity to5′-CGGGUCCAAGAUGGACGGCCA-3′ (SEQ ID NO:2) but maintains at least one CpGmotif. In some embodiments, the second strand comprises a non-guideregion, wherein the non-guide region comprises a nucleic acid sequencehaving more than about 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%identity to 5′-UGCUUGUCAACCACACCGACU-3′ (SEQ ID NO:8). In someembodiments, the second strand comprises a non-guide region, wherein thenon-guide region comprises a nucleic acid sequence having more thanabout 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99% identity to5′-UGCUUGUCAACCACACCGACU-3′ (SEQ ID NO:8) but maintains at least one CpGmotif.

In some embodiments, the RNAi comprises the nucleic acid sequence of SEQID NO:4. In some embodiments, the RNAi comprises a nucleic acid sequencehaving more than about 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%identity to SEQ ID NO:4. In some embodiments, the RNAi comprises anucleic acid sequence having more than about 75%, 80%, 85%, 90%, 95%,96%, 97%, 98%, 99% identity to SEQ ID NO:4 but maintains at least onesequence (e.g., in a seed sequence). In some embodiments, the RNAi ismiRNA-207. In other embodiments, the RNAi is miRNA-206.

In some embodiments, the RNAi comprises the nucleic acid sequence of SEQID NO: 10. In some embodiments, the RNAi comprises a nucleic acidsequence having more than about 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%,99% identity to SEQ ID NO:10. In some embodiments, the RNAi comprises anucleic acid sequence having more than about 75%, 80%, 85%, 90%, 95%,96%, 97%, 98%, 99% identity to SEQ ID NO: 10 but maintains at least oneCpG sequence (e.g., in a seed sequence). In some embodiments, the RNAiis miRNA-207. In some embodiments, the RNAi is miRNA-206.

A microRNA (miRNA) is known in the art as an RNA molecule that inducesRNAi in a cell comprising a short (e.g., 19-25 base pairs) sequence ofdouble-stranded RNA linked by a loop and containing one or moreadditional sequences of double-stranded RNA comprising one or morebulges (e.g., mispaired or unpaired base pairs). As used herein, theterm “miRNA” encompasses endogenous miRNAs as well as exogenous orheterologous miRNAs. In some embodiments. “miRNA” may refer to apri-miRNA or a pre-miRNA. During miRNA processing, a pri-miRNAtranscript is produced. The pri-miRNA is processed by Drosha-DGCR8 toproduce a pre-miRNA by excising one or more sequences to leave apre-miRNA with a 5′flanking region, a guide strand, a loop region, anon-guide strand, and a 3′flanking region; or a 5′flanking region, anon-guide strand, a loop region, a guide strand, and a 3′flankingregion. The pre-miRNA is then exported to the cytoplasm and processed byDicer to yield a siRNA with a guide strand and a non-guide (orpassenger) strand. The guide strand is then used by the RISC complex tocatalyze gene silencing, e.g., by recognizing a target RNA sequencecomplementary to the guide strand. Further description of miRNAs may befound, e.g., in WO 2008/150897. The recognition of a target sequence bya miRNA is primarily determined by pairing between the target and themiRNA seed sequence, e.g., nucleotides 1-8 (5′ to 3′) of the guidestrand (see, e.g., Boudreau, R. L. et al. (2013) Nucleic Acids Res.41:e9).

In the pri/pre-miRNA structure, the guide strand:non-guide strandinterface in a duplex is formed in part through complementary basepairing (e.g., Watson-Crick base pairing). However, in some embodiments,this complementary base pairing does not extend through the entireduplex. In some embodiments, a bulge in the interface may exist at oneor more nucleotide positions. As used herein, the term “bulge” may referto a region of nucleic acid that is non-complementary to the nucleicacid opposite it in a duplex. In some embodiments, the bulge is formedwhen the regions of complementary nucleic acids bind to each other,whereas the regions of central non-complementary region do not bind. Insome embodiments, the bulge is formed when the two strands of nucleicacid positioned between the two complementary regions are of differentlengths. As described below, a bulge may comprise 1 or more nucleotides.

During miRNA processing, the miRNA is cleaved at a cleavage siteadjacent to the guide strand:non-guide strand interface, thus releasingthe siRNA duplex of the guide and non-guide strands. In someembodiments, the miRNA comprises a bulge in the sense or antisensestrand adjacent to the cleavage site. To state another way, in someembodiments, the miRNA comprises a bulge in the guide or non-guidestrand adjacent to the seed sequence. See FIG. 1A.

In some embodiments, the miRNA comprises a bulge in the guide strandopposite the 5′ cleavage site of the mature non-guide strand. In someembodiments, the miRNA comprises a bulge opposite the 5′ nucleotide ofthe non-guide strand. In some embodiments, the miRNA comprises a bulgein the sense strand opposite the 3′ cleavage site of the mature guidestrand. In some embodiments, the miRNA comprises a bulge opposite the 3′nucleotide of the guide strand.

In some embodiments, the RNAi comprises a first strand and a secondstrand, wherein a) the first strand and the second form a duplex; b) thefirst strand comprises a guide region of at least 11 bases, wherein theguide region comprises a seed region comprising bases 1-N of the guidestrand, wherein N=7 or N=8; and c) the second strand comprises anon-guide region of at least 11 bases, wherein the non-guide regioncomprises a bulge sequence opposite of any one or more of bases 1-(N+2)of the guide region in the duplex. In some embodiments, wherein N=7 andthe bulge is opposite base 1, 2, 3, 4, 5, 6, 7, 8, or 9 of the guideregion. In other embodiments, N=8 and the bulge is opposite base 1, 2,3, 4, 5, 6, 7, 8, 9, or 10 of the guide region.

In some embodiments, the RNAi comprises a first strand and a secondstrand, wherein a) the first strand and the second form a duplex; b) thefirst strand comprises a guide region of at least 10 bases, wherein theguide region comprises a seed region comprising bases 1-N of the guidestrand, wherein N=7 or N=8; and c) the second strand comprises anon-guide region of at least 10 bases, wherein the non-guide regioncomprises a bulge sequence opposite of any one or more of bases 1-(N+1)of the guide region in the duplex. In some embodiments, wherein N=7 andthe bulge is opposite base 1, 2, 3, 4, 5, 6, 7, or 8 of the guideregion. In other embodiments, N=8 and the bulge is opposite base 1, 2,3, 4, 5, 6, 7, 8, or 9 of the guide region.

In some embodiments, the non-guide region comprises a bulge sequenceopposite of any one or more of bases 1-N of the guide region in theduplex. In some embodiments, N=7 and the bulge is opposite base 1, 2, 3,4, 5, 6 or 7 of the guide region. In other embodiments, N=8 and thebulge is opposite base 1, 2, 3, 4, 5, 6, 7 or 8 of the guide region.

In some embodiments, the RNAi comprises a first strand and a secondstrand, wherein a) the first strand and the second form a duplex, b) thefirst strand comprises a guide region of at least 9 bases, wherein theguide region comprises a seed region comprising bases 2-7 or 2-8 of theguide strand, and c) the second strand comprises a non-guide region ofat least 9 bases, wherein the non-guide region comprises a bulgesequence opposite of base 1 or base 9 of the guide region in the duplex.

In some embodiments, the RNAi comprises a first strand and a secondstrand, wherein a) the first strand and the second form a duplex, b) thefirst strand comprises a guide region of at least 9 bases, wherein theguide region comprises a seed region comprising bases 2-7 or 2-8 of theguide strand, and c) the second strand comprises a non-guide region ofat least 9 bases, wherein the non-guide region comprises a bulgesequence opposite of base 1 of the guide region in the duplex.

In some embodiments, the bulge is formed by one or more bases of thenon-guide strand in the duplex that lack a complementary base on theguide region, wherein the bulge is flanked by bases that do basepairwith the guide strand. In some embodiments, the bulge sequence has about1-10 nucleotides. In some embodiments, the bulge sequence has about 2-15nucleotides. In some embodiments, the bulge sequence has about 1, about2, about 3, about 4, about 5, about 6, about 7, about 8, about 9, about10, about 11, about 12, about 13, about 14, or about 15 nucleotides.

The safety of RNAi-based therapies can be hampered by the ability ofsmall inhibitory RNAs (siRNAs) to bind to unintended mRNAs and reducetheir expression, an effect known as off-target gene silencing.Off-targeting primarily occurs when the seed region (nucleotides 2-8 ofthe small RNA) pairs with sequences in 3′-UTRs of unintended mRNAs anddirects translational repression and destabilization of thosetranscripts. Reduced off-targeting RNAi may be designed by substitutingbases within the guide and nonguide sequences; e.g., by creating CpGmotifs. Potential substitutions that may result in a significantly loweroff-target score can be evaluated using the SiSPOTR algorithm, aspecificity-focused siRNA design algorithm which identifies candidatesequences with minimal off-targeting potentials and potent silencingcapacities (Boudreau et al, Nucleic Acids Res. 2013 January; 41(1) e9. Areduced SiSPOTR score predicts sequences that have a lower number ofpotential human off targets compared parent RNAi molecules. In someembodiments of the invention, the RNAi is improved to reduce off-targetgene silencing. In some embodiments, the RNAi comprises one or more CpGmotifs. In some embodiments, the RNAi comprises one or more CpG motifsin a seed region.

In some embodiments, the first strand and the second strand are linkedby means of a RNA (e.g., a RNA linker) capable of forming a loopstructure. As is commonly known in the art, an RNA loop structure (e.g.,a stem-loop or hairpin) is formed when an RNA molecule comprises twosequences of RNA that basepair together separated by a sequence of RNAthat does not base pair together. For example, a loop structure may formin the RNA molecule A-B-C if sequences A and C are complementary orpartially complementary such that they base pair together, but the basesin sequence B do not base pair together.

In some embodiments, the RNA capable of forming a loop structurecomprises from 4 to 50 nucleotides. In certain embodiments, the RNAcapable of forming a loop structure comprises 13 nucleotides. In someembodiments, the number of nucleotides in the RNA capable of forming aloop is from 4 to 50 nucleotides or any integer therebetween. In someembodiments, from 0-50% of the loop can be complementary to anotherportion of the loop. As used herein, the term “loop structure” is asequence that joins two complementary strands of nucleic acid. In someembodiments, 1-3 nucleotides of the loop structure are contiguous to thecomplementary strands of nucleic acid and may be complementary to 1-3nucleotides of the distal portion of the loop structure. For example,the three nucleotides at the 5′ end of the loop structure may becomplementary to the three nucleotides at the 3′ end of the loopstructure.

In some embodiments, nucleic acid encoding an RNAi of the presentdisclosure comprises a heterologous miRNA scaffold. In some embodiments,use of a heterologous miRNA scaffold is used to modulate miRNAexpression; for example, to increase miRNA expression or to decreasemiRNA expression. Any miRNA scaffold known in the art may be used. Insome embodiments, the miRNA scaffold is derived from a miR-155 scaffold(see, e.g., Lagos-Quintana, M. et al. (2002) Curr. Biol. 12:735-9 andthe Invitrogen™ BLOCK-iT™ Pol II miR RNAi expression vector kit fromLife Technologies, Thermo Fisher Scientific; Waltham, Mass.).

IV. Huntington's Disease and Experimental Models Thereof

Huntington's disease (HD) is an inherited neurodegenerative diseasecaused by an expansion of the CAG repeat in exon 1 of the huntingtingene (HTF). The resulting extension of the polyglutamine tract in theN-terminal region confers a toxic gain-of-function to the mutanthuntingtin protein (mHtt), mHtt toxicity may arise from the formation ofinsoluble mHtt-containing aggregates, transcriptional dysregulation, andperturbations in protein homeostasis, all of which can lead to neuronaldeath (Saudou et al. (1998) Cell, 95:55-66; Zuccato et al. (2003) Nat.Genet. 35:76-83; Schaffar et al. (2004) Mol. Cell. 15:95-105; Benn etal., (2008) J. Neurosci. 28:10720-10733). Pathological findings inpatients with HD include cortical thinning and a striking progressiveloss of striatal neurons (Rosas et al., (2002) Neurology 58:695-701).Disease onset typically occurs during the third to fourth decade oflife; symptoms include choreiform movements, impaired coordination,progressive dementia, and other psychiatric disturbances (Vonsattel etal., (1985) J. Neuropathol. Exp. Neurol. 44:559-577). In most cases,symptoms begin to appear between 30 and 40 years of age with subtledisruptions in motor skills, cognition, and personality. Over time,these progress into jerky, uncontrollable movements and loss of musclecontrol, dementia, and psychiatric illnesses such as depression,aggression, anxiety, and obsessive-compulsive behaviors. Death typicallyoccurs 10-15 years after the onset of symptoms. Less than 10% of HDcases involve a juvenile-onset form of the disease, characterized by afaster disease progression. It is thought that approximately 1 in 10,000Americans has HD.

Although the genetic basis of HD has been known for almost 20 years,current therapies are largely palliative and do not address theunderlying cause of the disease. This is likely due in part to the factthat the etiology of this disease is complex, with detrimental effectsobserved in a wide variety of cellular processes. Hence, the focus ofdrug development has been directed at addressing the primary offendingtrigger, namely, the mutant HTT gene itself.

Most cases of HD are associated with a trinucleotide CAG repeatexpansion in the HTT gene. The number of CAG repeats in the HTT gene isstrongly correlated with the manifestation of HD. For example,individuals with 35 or fewer repeats typically do not develop HD, butindividuals with between 27 and 35 repeats have a greater risk of havingoffspring with HD. Individuals with between 36 and 40-42 repeats have anincomplete penetrance of HD, whereas individuals with more than 40-42repeats show complete penetrance. Cases of juvenile-onset HD may beassociated with CAG repeat sizes of 60 or more.

The polyQ-expanded Htt protein resulting from this CAG repeat expansionis associated with cellular aggregates or inclusion bodies,perturbations to protein homeostasis, and transcriptional dysregulation.While these toxic phenotypes may be seen throughout the body, they aremost typically associated with neuronal cell death in the CNS. HDpatients often display cortical thinning and a striking, progressiveloss of striatal neurons. The striatum appears to be the most vulnerableregion of the brain in HD (particularly the striatal medium spinyneurons), with early effects seen in the putamen and caudate nucleus.Cell death in the striatal spiny neurons, increased numbers ofastrocytes, and activation of microglia are observed in the brains of HDpatients. HD may also affect certain regions of the hippocampus,cerebral cortex, thalamus, hypothalamus, and cerebellum.

Proposed approaches to blocking Htt expression include the use ofantisense oligonucleotides (ASOs) as well as RNA interference (RNAi)that uses either duplex RNAs (dsRNAs) or chemically modifiedsingle-stranded RNAs (ssRNAs) (Harper et al., (2005) Proc. Natl. Acad.Sci. USA 102:5820-5825; DiFiglia et al., (2007) Proc. Natl. Acad. Sci.USA 104:17204-17209; Boudreau et al., (2009b) Mol. Ther. 17:1053-1063;Drouet et al., (2009) Ann. Neurol. 65:276-285; Sah et al., (2011) J.Clin. Invest. 121:500-507; Matsui et al., (2012) Drug Discov. Today17:443-450; Yu et al., (2012) Cell 150:895-908). However, hurdles totranslating an ASO approach into the clinic may include the need toincorporate a device to facilitate repeated and chronic infusions of ASOinto the CNS, and to the need to adequately distribute the drug totarget regions in a large brain.

To circumvent these potential issues with ASO, employing AAV-mediatedexpression of an RNAi (e.g., siRNA), which offers the potential forincreased safety, increased efficiency, and longer-lasting efficacy, maybe advantageous. As HD patients express both mutant and wild-type Httalleles, a majority of siRNA targeting sequences will likely degradeboth alleles. However, non-allele-specific Htt silencing in HD mice hasbeen shown to be well tolerated and can afford the same benefit asreducing mutant Htt alone (Boudreau et al., (2009b) Mol. Ther.17:1053-1063; Drouet et al., (2009) Ann. Neurol. 65:276-285;Kordasiewicz et al., (2012) Neuron 74(6):1031-1044). Moreover, thepartial and sustained suppression of wild-type Htt in the putamen ofnon-human primates following AAV-mediated RNAi reportedly did not haveany untoward effects, which suggests that the adult brain can toleratereduced levels of wild-type Htt (McBride et al., (2011) Mol. Ther.19:2152-2162; Grondin et al., (2012) Brain 135:1197-1209).

Animal models of HD may be used to test potential therapeuticstrategies, such as the compositions and methods of the presentdisclosure. Mouse models for HD are known in the art. These includemouse models with fragments of mutant HT such as the R6/1 and N171-82QHD mice (Harper et al., (2005) Proc. Natl. Acad. Sci. USA 102:5820-5825,Rodriguez-Lebron et al., (2005) Mol. Ther. 12:618-633, Machida et al.,(2006) Biochem. Biophys. Res. Commun. 343:190-197). Another example of amouse HD model described herein is the YAC128 mouse model. This modelbears a yeast artificial chromosome (YAC) expressing a mutant human H7Tgene with 128 CAG repeats, and YAC128 mice exhibit significant andwidespread accumulation of Htt aggregates in the striatum by 12 monthsof age (Slow et al., (2003) Hum. Mol. Genet. 12:1555-1567, Pouladi etal., (2012) Hum. Mol. Genet. 21:2219-2232).

Other animal models for HD may also be used. For example, transgenic rat(von Horsten, S. et al. (2003) Hum. Mol. Genet. 12:617-24) and rhesusmonkey (Yang, S. H. et al. (2008) Nature 453:921-4) models have beendescribed. Non-genetic models are also known. These most often involvethe use of excitotoxic compounds (such as quinolinic acid or kainicacid) or mitochondrial toxins (such as 3-nitropropionic acid and malonicacid) to induce striatal neuron cell death in rodents or non-humanprimates (for more description and references, see Ramaswamy, S. et al.(2007) ILAR J. 48:356-73).

V. Methods to Treat Huntington's Disease

In some aspects, the invention provides methods and compositions fortreating Huntington's disease in a mammal comprising administering tothe mammal a pharmaceutical composition of the present disclosure (e.g.,a pharmaceutical composition comprising a viral particle of the presentdisclosure). In some aspects, the invention provides methods andcompositions for inhibiting the expression of htt in a mammal withHuntington's disease comprising administering to the mammal apharmaceutical composition of the present disclosure (e.g., apharmaceutical composition comprising a viral particle of the presentdisclosure). In some aspects, the invention provides methods andcompositions for inhibiting the accumulation of htt in a cell of amammal with Huntington's disease comprising administering to the mammala pharmaceutical composition of the present disclosure (e.g., apharmaceutical composition comprising a viral particle of the presentdisclosure).

In some aspects, the invention provides methods and compositions forameliorating a symptom of HD, comprising administration of an effectiveamount of recombinant viral particles comprising a vector encoding anRNAi of the present disclosure to the brain of a mammal. In someembodiments, the symptoms of HD include, but are not limited to, chorea,rigidity, uncontrollable body movements, loss of muscle control, lack ofcoordination, restlessness, slowed eye movements, abnormal posturing,instability, ataxic gait, abnormal facial expression, speech problems,difficulties chewing and/or swallowing, disturbance of sleep, seizures,dementia, cognitive deficits (e.g., diminished abilities related toplanning, abstract thought, flexibility, rule acquisition, interpersonalsensitivity, self-control, attention, learning, and memory), depression,anxiety, changes in personality, aggression, compulsive behavior,obsessive-compulsive behavior, hypersexuality, psychosis, apathy,irritability, suicidal thoughts, weight loss, muscle atrophy, heartfailure, reduced glucose tolerance, testicular atrophy, andosteoporosis.

In some aspects, the invention provides methods to prevent or delayprogression of HD. Autosomal dominant HD is a genetic disease that canbe genotyped. For example, the number of CAG repeats in HT may bedetermined by PCR-based repeat sizing. This type of diagnosis may beperformed at any stage of life through directly testing juveniles oradults (e.g., along with presentation of clinical symptoms), prenatalscreening or prenatal exclusion testing (e.g., by chorionic villussampling or amniocentesis), or preimplantation screening of embryos. Assuch, the methods described herein may be used as a prophylactictreatment of HD since diagnosis may occur before symptom onset. Forexample, HD may be diagnosed by genetic testing (prenatal testing,testing at birth, etc.) and treated prophylactically (e.g., using a rAAVparticle described herein) prior to symptom onset (e.g., CNS cell loss)to prevent HD symptom onset and/or progression. HD patients may displayshrinkage of the caudate nuclei and/or putamen and/or cortex and/orenlarged ventricles as seen by brain imaging. These symptoms, combinedwith a family history of HD and/or clinical symptoms, may indicate HD.

Means for determining amelioration of the symptoms of HD are known inthe art. For example, the Unified Huntington's Disease Rating Scale(UHDRS) may be used to assess motor function, cognitive function,behavioral abnormalities, and functional capacity (see, e.g., HuntingtonStudy Group (1996) Movement Disorders 11:136-42). This rating scale wasdeveloped to provide a uniform, comprehensive test for multiple facetsof the disease pathology, incorporating elements from tests such as theHD Activities and Daily Living Scale, Marsden and Quinn's choreaseverity scale, the Physical Disability and Independence scales, the HDmotor rating scale (HDMRS), the HD functional capacity scale (HDFCS),and the quantitated neurological exam (QNE). Other test useful fordetermining amelioration of HD symptoms may include without limitationthe Montreal Cognitive Assessment, brain imaging (e.g., MRI), CategoryFluency Test, Trail Making Test, Map Search, Stroop Word Reading Test,Speeded Tapping Task, and the Symbol Digit Modalities Test.

In some aspects of the invention, the methods and compositions are usedfor the treatment of humans with HD. As described above, HD is inheritedin an autosomal dominant manner and caused by CAG repeat expansion inthe HTT gene. Juvenile-onset HD is most often inherited from thepaternal side. Huntington disease-like phenotypes have also beencorrelated with other genetic loci, such as HDL1, PRNP, HDL2, HDL3, andHDL4. It is thought that other genetic loci may modify the manifestationof HD symptoms, including mutations in the GRIN2A, GRIN2B, MSX1, GRIK2,and APOE genes.

In some aspects, the invention provides an improved RNAi for targetinghtt mRNA in a mammal with Huntington's disease. In some embodiments, theRNAi comprises a first strand comprising a first nucleic acid comprisingthe sequence 5′-UGGCCGUCCAUCUUGGACCCG-3′ (SEQ ID NO:1) and a secondstrand comprising a second nucleic acid comprising the sequence5′-CGGGUCCAAGAUGGACGGCCA-3′ (SEQ ID NO:2). An RNAi described herein(e.g., as part of a rAAV vector) may find use, inter alia, in treatingHuntington's disease.

In some aspects, the invention provides an improved RNAi for targetinghtt mRNA in a mammal with Huntington's disease. In some embodiments, theRNAi comprises a first strand comprising a first nucleic acid comprisingthe sequence 5′-AGUCGGUGUGGUUGACAAGCA-3′ (SEQ ID NO:7) and a secondstrand comprising a second nucleic acid comprising the sequence5′-UGCUUGUCAACCACACCGACU-3′ (SEQ ID NO:8). An RNAi described herein(e.g., as part of a rAAV vector) may find use, inter alia, in treatingHuntington's disease.

In some embodiments of the invention, the RNAi is improved to reduceoff-target gene silencing. In some embodiments, the RNAi comprises oneor more CpG motifs. In some embodiments, the RNAi comprises one or moreCpG motifs in a seed region.

In some embodiments, the first strand comprises a nucleic acid sequencehaving more than about any of 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98% or99% identity to SEQ ID NO:1 but maintains the CpG motif. In someembodiments, the second strand comprises a nucleic acid sequence havingmore than about any of 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98% or 99%identity to SEQ ID NO:2 but maintains the CpG motif.

In some embodiments, the first strand comprises a nucleic acid sequencehaving more than about any of 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98% or99% identity to SEQ ID NO:7 but maintains the CpG motif. In someembodiments, the second strand comprises a nucleic acid sequence havingmore than about any of 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98% or 99%identity to SEQ ID NO:8 but maintains the CpG motif.

In some embodiments, the RNAi is a small inhibitory RNA (siRNA), amicroRNA (miRNA), or a small hairpin RNA (shRNA). A small inhibitory orinterfering RNA (siRNA) is known in the art as a double-stranded RNAmolecule of approximately 19-25 (e.g., 19-23) base pairs in length thatinduces RNAi in a cell. A small hairpin RNA (shRNA) is known in the artas an RNA molecule comprising approximately 19-25 (e.g., 19-23) basepairs of double stranded RNA linked by a short loop (e.g., ˜4-11nucleotides) that induces RNAi in a cell.

In some embodiments, the miRNA comprises a guide sequence that is about90% identical to SEQ ID NO:1. In some embodiments, the miRNA comprises aguide sequence that is about any of 90% identical, 91% identical, 92%identical, 93% identical, 94% identical, 95% identical, 96% identical,97% identical, 98% identical, 99% identical, or 100% identical to SEQ IDNO:1.

In some embodiments, the miRNA comprises a non-guide sequence that isabout 90% identical to SEQ ID NO:2. In some embodiments, the miRNAcomprises a non-guide sequence that is about any of 90% identical, 91%identical, 92% identical, 93% identical, 94% identical, 95% identical,96% identical, 97% identical, 98% identical, 99% identical, or 100%identical to SEQ ID NO:2.

In some embodiments, the miRNA comprises a guide sequence that is about90% identical to SEQ ID NO:7. In some embodiments, the miRNA comprises aguide sequence that is about any of 90% identical, 91% identical, 92%identical, 93% identical, 94% identical, 95% identical, 96% identical,97% identical, 98% identical, 99% identical, or 100% identical to SEQ IDNO:7.

In some embodiments, the miRNA comprises a non-guide sequence that isabout 90% identical to SEQ ID NO:8. In some embodiments, the miRNAcomprises a non-guide sequence that is about any of 90% identical, 91%identical, 92% identical, 93% identical, 94% identical, 95% identical,96% identical, 97% identical, 98% identical, 99% identical, or 100%identical to SEQ ID NO:8.

In some embodiments, the first strand and the second strand are linkedby means of RNA capable of forming a loop structure. As is commonlyknown in the art, an RNA loop structure (e.g., a stem-loop or hairpin)is formed when an RNA molecule comprises two sequences of RNA thatbasepair together separated by a sequence of RNA that does not base pairtogether. For example, a loop structure may form in the RNA moleculeA-B-C if sequences A and C are complementary or partially complementarysuch that they base pair together, but the bases in sequence B do notbase pair together.

In some embodiments, the RNA capable of forming a loop structurecomprises from 4 to 50 nucleotides. In certain embodiments, the RNAcapable of forming a loop structure comprises 13 nucleotides. In certainembodiments, the RNA capable of forming a loop structure comprises thenucleotide sequence GUUUUGGCCACUGACUGAC (SEQ ID NO: 13). In someembodiments, the vector genome comprises a nucleotide sequence that isat least about any of 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%,98%, or 99% identical to the sequence of SEQ ID NO:13.

In some aspects, the invention provides methods comprising administeringto a mammal (e.g., a mammal with HD) an RNAi comprising a first strandcomprising a first nucleic acid comprising the sequence5′-UGGCCGUCCAUCUUGGACCCG-3′ (SEQ ID NO: 1) and a second strandcomprising a second nucleic acid comprising the sequence5′-CGGGUCCAAGAUGGACGGCCA-3′ (SEQ ID NO:2). In some embodiments, arecombinant viral particle comprises the RNAi. In some embodiments, therecombinant viral particle is an AAV particle encapsidating a rAAVvector, an adenovirus particle encapsidating a recombinant adenoviralvector, a lentiviral particle encapsidating a recombinant lentiviralvector or an HSV particle encapsidating a recombinant HSV vector whereinthe rAAV vector, the adenoviral vector, the lentiviral vector or the HSVvector encodes the RNAi.

In some aspects, the invention provides methods comprising administeringto a mammal (e.g., a mammal with HD) an RNAi comprising a first nucleicacid comprising the sequence 5′-AGUCGGUGUGGUUGACAAGCA-3′ (SEQ ID NO:7)and a second strand comprising a second nucleic acid comprising thesequence 5′-UGCUUGUCAACCACACCGACU-3′ (SEQ ID NO:8). In some embodiments,a recombinant viral particle comprises the RNAi. In some embodiments,the recombinant viral particle is an AAV particle encapsidating a rAAVvector, an adenovirus particle encapsidating a recombinant adenoviralvector, a lentiviral particle encapsidating a recombinant lentiviralvector or an HSV particle encapsidating a recombinant HSV vector whereinthe rAAV vector, the adenoviral vector, the lentiviral vector or the HSVvector encodes the RNAi.

In some embodiments, delivery of recombinant viral particles is byinjection of viral particles to the brain. In some embodiments, deliveryof recombinant viral particles is by injection of viral particles to thestriatum. Intrastriatal administration delivers recombinant viralparticles to an area of the brain, the striatum (including the putamenand caudate nucleus), that is highly affected by HD. In addition, andwithout wishing to be bound to theory, it is thought that recombinantviral particles (e.g., rAAV particles) injected into the striatum may bealso dispersed (e.g., through retrograde transport) to other areas ofthe brain, including without limitation projection areas (e.g., thecortex). In some embodiments, the recombinant viral particles aredelivered by convection enhanced delivery (e.g., convection enhanceddelivery to the striatum).

In some aspects, the invention provides methods for treatingHuntington's disease in a mammal comprising administering to the mammalthe pharmaceutical composition of the present disclosure. In someaspects, the invention provides methods for inhibiting the accumulationof htt in a cell of a mammal with Huntington's disease comprisingadministering to the mammal the pharmaceutical composition of thepresent disclosure. In some aspects, the invention provides methods forinhibiting the expression of htt in a mammal with Huntington's diseasecomprising administering to the mammal the pharmaceutical composition ofthe present disclosure. In some embodiments, the htt is a mutant htt(e.g., an htt comprising greater than 35, greater than 36, greater than37, greater than 38, greater than 39, greater than 40, greater than 41,or greater than 42 CAG repeats). In some embodiments, expression and/oraccumulation of a wild-type htt is also inhibited. As described herein,and without wishing to be bound to theory, it is thought that inhibitionof expression and/or accumulation of mutant htt in a mammal with HD ishighly beneficial, but the inhibition of expression and/or accumulationof wild-type htt in the same mammal as a side effect (e.g., of an RNAiof the present disclosure) may be well tolerated (e.g., produces few orno unintended side effects).

In some embodiments, a cell comprises a vector (e.g., a vectorcomprising an expression construct encoding an RNAi of the presentdisclosure). In some embodiments, the vector is a rAAV vector. In someembodiments, the vector is a recombinant adenoviral vector, arecombinant lentiviral vector or a recombinant herpes simplex virus(HSV) vector. In some embodiments, the cell is a central nervous system(CNS) cell.

In some embodiments, the administration of an effective amount ofrecombinant viral particles comprising a vector encoding an RNAi of thepresent disclosure transduces neurons (e.g., striatal neurons, such asspiny neurons) at or near the site of administration. In someembodiments, more than about any of 5%, 10%, 15%, 20%, 25%, 30%, 35%,40%, 45%, 50%, 55%, 60%, 65%, 70%, 75% or 100% of neurons aretransduced. In some embodiments, about 5% to about 100%, about 10% toabout 50%, about 10% to about 30%, about 25% to about 75%, about 25% toabout 50%, or about 30% to about 50% of the neurons are transduced.Methods to identify neurons transduced by recombinant viral particlesexpressing miRNA are known in the art; for example,immunohistochemistry, RNA detection (e.g., qPCR, Northern blotting,RNA-seq, in situ hybridization, and the like) or the use of aco-expressed marker such as enhanced green fluorescent protein can beused to detect expression.

In some embodiments of the invention, the methods compriseadministration to the brain of a mammal an effective amount ofrecombinant viral particles comprising a vector encoding an RNAi of thepresent disclosure for treating a mammal, e.g., a human, with HD. Insome embodiments, the composition is injected to one or more locationsin the brain to allow expression of an RNAi of the present disclosure inat least the neurons. In some embodiments, the composition is injectedinto any one of one, two, three, four, five, six, seven, eight, nine,ten or more than ten locations in the brain. In some embodiments, thecomposition is injected into the striatum. In some embodiments, thecomposition is injected into the dorsal striatum. In some embodiments,the composition is injected into the putamen. In some embodiments, thecomposition is injected into the caudate nucleus. In some embodiments,the composition is injected into the putamen and into the caudatenucleus.

In some embodiments, the recombinant viral particles are administered toone hemisphere of the brain. In some embodiments, the recombinant viralparticles are administered to both hemispheres of the brain.

In some embodiments the recombinant viral particles are administered tomore than one location simultaneously or sequentially. In someembodiment, multiple injections of recombinant viral particles are nomore than one hour, two hours, three hours, four hours, five hours, sixhours, nine hours, twelve hours or 24 hours apart.

In some embodiments, the invention provides a method for treating ahuman with HD by administering an effective amount of a pharmaceuticalcomposition comprising a recombinant viral vector encoding an RNAi ofthe present disclosure to suppress the activity of a mutant HTT. In someembodiments, the pharmaceutical composition comprises one or morepharmaceutically acceptable excipients.

In some embodiments, the methods comprise administering an effectiveamount of a pharmaceutical composition comprising a recombinant viralvector encoding an RNAi of the present disclosure to suppress theactivity of a mutant HTT. In some embodiments, the viral titer of theviral particles (e.g., rAAV particles) is at least about any of 5×10¹²,6×10¹², 7×10¹², 8×10¹², 9×10¹², 10×10¹², 11×10¹², 15×10¹², 20×10¹²,25×10¹², 30×10¹², or 50×10¹² genome copies/mL. In some embodiments, theviral titer of the viral particles (e.g., rAAV particles) is about anyof 5×10¹² to 6×10¹², 6×10¹² to 7×10¹², 7×10¹² to 8×10¹²8×10¹² to 9×10¹²,9×10¹² to 10×10¹², 10×10¹² to 11×10¹², 11×10¹² to 15×10¹², 15×10¹² to20×10¹², 20×10¹² to 25×10¹², 25×10¹² to 30×10¹², 30×10¹² to 50×10¹², or50×10¹² to 100×10¹² genome copies/mL. In some embodiments, the viraltiter of the viral particles (e.g., rAAV particles) is about any of5×10¹² to 10×10¹², 10×10¹² to 25×10¹², or 25×10¹² to 50×10′² genomecopies/mL. In some embodiments, the viral titer of the viral particles(e.g., rAAV particles) is at least about any of 5×10⁹, 6×10⁹, 7×10⁹,8×10⁹, 9×10, 10×10⁹, 11×10⁹, 15×10⁹, 20×10⁹, 25×10⁹, 30×10⁹, or 50×10⁹transducing units/mL. In some embodiments, the viral titer of the viralparticles (e.g., rAAV particles) is about any of 5×10⁹ to 6×10⁹, 6×10⁹to 7×10⁹, 7×10⁹ to 8×10⁹, 8×10⁹ to 9×10⁹, 9×10⁹ to 10×10⁹, 10×10⁹ to11×10⁹, 11×10⁹ to 1×10⁹, 15×10⁹ to 20×10⁹, 20×10⁹ to 25×10⁹, 25×10⁹ to30×10⁹, 30×10⁹ to 50×10⁹ or 50×10⁹ to 100×10⁹ transducing units/mL. Insome embodiments, the viral titer of the viral particles (e.g., rAAVparticles) is about any of 5×10⁹ to 10×10⁹, 10×10⁹ to 15×10⁹, 15×10⁹ to25×10⁹, or 25×10⁹ to 50×10⁹ transducing units/mL. In some embodiments,the viral titer of the viral particles (e.g., rAAV particles) is atleast any of about 5×10¹⁰, 6×10¹⁰, 7×10¹⁰, 8×10¹⁰, 9×10¹⁰, 10×10¹⁰,11×10¹⁰, 15×10¹⁰, 20×10¹⁰, 25×10¹⁰, 30×10¹⁰, 40×10¹⁰, or 50×10¹⁰infectious units/mL. In some embodiments, the viral titer of the viralparticles (e.g., rAAV particles) is at least any of about 5×10¹⁰ to6×10¹⁰, 6×10¹⁰ to 7×10¹⁰, 7×10¹⁰ to 8×10¹⁰, 8×10¹⁰ to 9×10¹⁰, 9×10¹⁰ to10×10¹⁰, 10×10¹⁰ to 11×10¹⁰, 11×10¹⁰ to 15×10¹⁰, 15×10¹⁰ to 20×10¹⁰,20×10¹⁰ to 25×10¹⁰, 25×10¹⁰ to 30×10¹⁰, 30×10¹⁰ to 40×10¹⁰, 40×10¹⁰ to50×10¹⁰, or 50×10¹⁰ to 100×10¹⁰ infectious units/mL. In someembodiments, the viral titer of the viral particles (e.g., rAAVparticles) is at least any of about 5×10¹⁰ to 10×10¹⁰, 10×10¹⁰ to15×10¹⁰, 15×10¹⁰ to 25×10¹⁰, or 25×10¹⁰ to 50×10¹⁰ infectious units/mL.

In some embodiments, the dose of viral particles administered to theindividual is at least about any of 1×10⁸ to about 1×10¹³ genomecopies/kg of body weight. In some embodiments, the dose of viralparticles administered to the individual is about any of 1×10⁸ to about1×10¹³ genome copies/kg of body weight.

In some embodiments, the total amount of viral particles administered tothe individual is at least about any of 1×10⁹ to about 1×10¹⁴ genomecopies. In some embodiments, the total amount of viral particlesadministered to the individual is about any of 1×10⁹ to about 1×10¹⁴genome copies.

In some embodiments of the invention, the volume of the compositioninjected to the striatum is more than about any one of 1 μl, 2 μl, 3 μl,4 μl, 5 μl, 6 μl, 7 μl, 8 μl, 9 μl, 10 μl, 15 μl, 20 μl, 25 μl, 50 μl,75 μl, 100 μl, 200 μl, 300 μl, 400 μl, 500 μl, 600 μl, 700 μl, 800 μl,900 μl, or 1 mL, or any amount therebetween.

In some embodiments, a first volume of the composition is injected intoa first region of the brain, and a second volume of the composition isinjected into a second region of the brain. For example, in someembodiments, a first volume of the composition is injected into thecaudate nucleus, and a second volume of the composition is injected intothe putamen. In some embodiments, a 1× volume of the composition isinjected into the caudate nucleus, and a 1.5×, 2×, 2.5×, 3×, 3.5×, or 4×volume of the composition is injected into the putamen, where X is avolume that is more than about any one of 1 μl, 2 μl, 3 μl, 4 μl, 5 μl,6 μl, 7 μl, 8 μl, 9 μl, 10 μl, 15 μl, 20 μl, 25 μl, 50 μl, 75 μl, 100μl, 200 μl, 300 μl, 400 μl, 500 μl, 600 μl, 700 μl, 800 μl, 900 μl, or 1mL, or any amount therebetween.

Compositions of the invention (e.g., recombinant viral particlescomprising a vector encoding an RNAi of the present disclosure) can beused either alone or in combination with one or more additionaltherapeutic agents for treating HD. The interval between sequentialadministration can be in terms of at least (or, alternatively, lessthan) minutes, hours, or days.

V. RNAi Expression Constructs and Vectors

The invention provides expression constructs, vectors and viralparticles for expression of the RNAi described herein.

In some embodiments, nucleic acid encoding an RNAi of the presentdisclosure comprises a heterologous miRNA scaffold. In some embodiments,use of a heterologous miRNA scaffold is used to modulate miRNAexpression; for example, to increase miRNA expression or to decreasemiRNA expression. Any miRNA scaffold known in the art may be used. Insome embodiments, the miRNA scaffold is derived from a miR-155 scaffold(see, e.g., Lagos-Quintana, M. et al. (2002) Curr. Biol. 12:735-9 andthe Invitrogen™ BLOCK-iT™ Pol II miR RNAi expression vector kit fromLife Technologies, Thermo Fisher Scientific; Waltham, Mass.). In someembodiments, nucleic acid encoding an RNAi of the present disclosurecomprises a miRNA scaffold. In some embodiments, miRNA scaffold isprovided by SEQ ID NO: 14.

In some embodiments, the RNAi targets RNA encoding a polypeptideassociated with Huntington's disease (e.g., mutant HTT). Without wishingto be bound to theory, it is thought that an RNAi may be used to reduceor eliminate the expression and/or activity of a polypeptide whosegain-of-function has been associated with Huntington's disease (e.g.,mutant HT).

In some embodiments, the transgene (e.g., an RNAi of the presentdisclosure) is operably linked to a promoter. Exemplary promotersinclude, but are not limited to, the cytomegalovirus (CMV) immediateearly promoter, the RSV LTR, the MoMLV LTR, the phosphoglyceratekinase-1 (PGK) promoter, a simian virus 40 (SV40) promoter and a CK6promoter, a transthyretin promoter (TTR), a TK promoter, a tetracyclineresponsive promoter (TRE), an HBV promoter, an hAAT promoter, a LSPpromoter, chimeric liver-specific promoters (LSPs), the E2F promoter,the telomerase (hTERT) promoter; the cytomegalovirus enhancer/chickenbeta-actin/Rabbit β-globin promoter (CAG promoter; Niwa et al., Gene,1991, 108(2):193-9) and the elongation factor 1-alpha promoter(EFl-alpha) promoter (Kim et al., Gene, 1990, 91(2):217-23 and Guo etal., Gene Ther., 1996, 3(9):802-10). In some embodiments, the promotercomprises a human β-glucuronidase promoter or a cytomegalovirus enhancerlinked to a chicken β-actin (CBA) promoter. The promoter can be aconstitutive, inducible or repressible promoter. In some embodiments,the invention provides a recombinant vector comprising nucleic acidencoding a heterologous transgene of the present disclosure operablylinked to a CBA promoter. Exemplary promoters and descriptions may befound, e.g., in U.S. PG Pub. 20140335054. In some embodiments, thepromoter is a CBA promoter, a minimum CBA promoter, a CMV promoter or aGUSB promoter.

Examples of constitutive promoters include, without limitation, theretroviral Rous sarcoma virus (RSV) LTR promoter (optionally with theRSV enhancer), the cytomegalovirus (CMV) promoter (optionally with theCMV enhancer) [see, e.g., Boshart et al, Cell, 41:521-530 (1985)], theSV40 promoter, the dihydrofolate reductase promoter, the β-actinpromoter, the phosphoglycerol kinase (PGK) promoter, and the EFlapromoter [Invitrogen].

Inducible promoters allow regulation of gene expression and can beregulated by exogenously supplied compounds, environmental factors suchas temperature, or the presence of a specific physiological state, e.g.,acute phase, a particular differentiation state of the cell, or inreplicating cells only. Inducible promoters and inducible systems areavailable from a variety of commercial sources, including, withoutlimitation, Invitrogen, Clontech and Ariad. Many other systems have beendescribed and can be readily selected by one of skill in the art.Examples of inducible promoters regulated by exogenously suppliedpromoters include the zinc-inducible sheep metallothionine (MT)promoter, the dexamethasone (Dex)-inducible mouse mammary tumor virus(MMTV) promoter, the T7 polymerase promoter system (WO 98/10088); theecdysone insect promoter (No et al, Proc. Natl. Acad. Sci. USA,93:3346-3351 (1996)), the tetracycline-repressible system (Gossen et al,Proc. Natl. Acad. Sci. USA, 89:5547-5551 (1992)), thetetracycline-inducible system (Gossen et al, Science, 268:1766-1769(1995), see also Harvey et al, Curr. Opin. Chem. Biol., 2:512-518(1998)), the RU486-inducible system (Wang et al, Nat. Biotech.,15:239-243 (1997) and Wang et al. Gene Ther., 4:432-441 (1997)) and therapamycin-inducible system (Magari et al, J. Clin. Invest.,100:2865-2872 (1997)). Still other types of inducible promoters whichmay be useful in this context are those which are regulated by aspecific physiological state. e.g., temperature, acute phase, aparticular differentiation state of the cell, or in replicating cellsonly.

In another embodiment, the native promoter, or fragment thereof, for thetransgene will be used. The native promoter may be preferred when it isdesired that expression of the transgene should mimic the nativeexpression. The native promoter may be used when expression of thetransgene must be regulated temporally or developmentally, or in atissue-specific manner, or in response to specific transcriptionalstimuli. In a further embodiment, other native expression controlelements, such as enhancer elements, polyadenylation sites or Kozakconsensus sequences may also be used to mimic the native expression.

In some embodiments, the regulatory sequences impart tissue-specificgene expression capabilities. In some cases, the tissue-specificregulatory sequences bind tissue-specific transcription factors thatinduce transcription in a tissue specific manner. Such tissue-specificregulatory sequences (e.g., promoters, enhancers, etc.) are well knownin the art. Exemplary tissue-specific regulatory sequences include, butare not limited to the following tissue specific promoters: neuronalsuch as neuron-specific enolase (NSE) promoter (Andersen et al., Cell.Mol. Neurobiol., 13:503-15 (1993)), neurofilament light-chain genepromoter (Piccioli et al., Proc. Natl. Acad. Sci. USA. 88:5611-5(1991)), and the neuron-specific vgf gene promoter (Piccioli et al.,Neuron, 15:373-84 (1995)). In some embodiments, the tissue-specificpromoter is a promoter of a gene selected from: neuronal nuclei (NeuN),glial fibrillary acidic protein (GFAP), adenomatous polyposis coli(APC), and ionized calcium-binding adapter molecule 1 (lba-1). Otherappropriate tissue specific promoters will be apparent to the skilledartisan. In some embodiments, the promoter is a chicken Beta-actin (CBA)promoter.

In some embodiments, the promoter expresses the heterologous nucleicacid in a cell of the CNS. As such, in some embodiments, a therapeuticpolypeptide or a therapeutic nucleic acid of the invention may be usedto treat a disorder of the CNS. In some embodiments, the promoterexpresses the heterologous nucleic acid in a brain cell. A brain cellmay refer to any brain cell known in the art, including withoutlimitation a neuron (such as a sensory neuron, motor neuron,interneuron, dopaminergic neuron, medium spiny neuron, cholinergicneuron, GABAergic neuron, pyramidal neuron, etc.), a glial cell (such asmicroglia, macroglia, astrocytes, oligodendrocytes, ependymal cells,radial glia, etc.), a brain parenchyma cell, microglial cell, ependemalcell, and/or a Purkinje cell. In some embodiments, the promoterexpresses the heterologous nucleic acid in a neuron and/or glial cell.In some embodiments, the neuron is a medium spiny neuron of the caudatenucleus, a medium spiny neuron of the putamen, a neuron of the cortexlayer IV and/or a neuron of the cortex layer V.

Various promoters that express transcripts (e.g., a heterologoustransgene) in CNS cells, brain cells, neurons, and glial cells are knownin the art and described herein. Such promoters can comprise controlsequences normally associated with the selected gene or heterologouscontrol sequences. Often, useful heterologous control sequences includethose derived from sequences encoding mammalian or viral genes. Examplesinclude, without limitation, the SV40 early promoter, mouse mammarytumor virus LTR promoter, adenovirus major late promoter (Ad MLP), aherpes simplex virus (HSV) promoter, a cytomegalovirus (CMV) promotersuch as the CMV immediate early promoter region (CMVIE), a Rous sarcomavirus (RSV) promoter, synthetic promoters, hybrid promoters, and thelike. In addition, sequences derived from nonviral genes, such as themurine metallothionein gene, may also be used. Such promoter sequencesare commercially available from, e.g., Stratagene (San Diego, Calif.).CNS-specific promoters and inducible promoters may be used. Examples ofCNS-specific promoters include without limitation those isolated fromCNS-specific genes such as myelin basic protein (MBP), glial fibrillaryacid protein (GFAP), and neuron specific enolase (NSE). Examples ofinducible promoters include DNA responsive elements for ecdysone,tetracycline, metallothionein, and hypoxia, inter alia.

The present invention contemplates the use of a recombinant viral genomefor introduction of one or more nucleic acid sequences encoding for aRNAi as described herein or packaging into an AAV viral particle. Therecombinant viral genome may include any element to establish theexpression of a RNAi, for example, all or a functional portion of apromoter, an intron (e.g., a chimeric intron)), a heterologous nucleicacid, an ITR, a ribosome binding element, terminator, enhancer,selection marker, intron, polyA signal, and/or origin of replication. Insome embodiments, the rAAV vector comprises one or more of an enhancer,an intron (e.g., a splice donor/splice acceptor pair), a matrixattachment site, or a polyadenylation signal. A variety of introns foruse in the invention are known to those of skill in the art, and includethe MVM intron, the F IX truncated intron 1, the β-globinSD/immunoglobin heavy chain SA, the adenovirus SD/immunoglobin SA, theSV40 late SD/SA (19S/16S), and the hybrid adenovirus SD/IgG SA. (Wu etal. 2008, Kurachi et al., 1995, Choi et al. 2014), Wong et al. 1985, Yewet al. 1997, Huang and Gorman (1990).

In some embodiments, the administration of an effective amount of rAAVparticles comprising a vector encoding a RNAi transduces cells (e.g.,CNS cells, brain cells, neurons, and/or glial cells) at or near the siteof administration (e.g., the striatum and/or cortex) or more distal tothe site of administration. In some embodiments, more than about any of5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%or 100% of neurons are transduced. In some embodiments, about 5% toabout 100%, about 10% to about 50%, about 10% to about 30%, about 25% toabout 75%, about 25% to about 50%, or about 30% to about 50% of theneurons are transduced. Methods to identify neurons transduced byrecombinant viral particles expressing miRNA are known in the art; forexample, immunohistochemistry, RNA detection (e.g., qPCR, Northernblotting, RNA-seq, in situ hybridization, and the like) or the use of aco-expressed marker such as enhanced green fluorescent protein can beused to detect expression.

In some aspects, the invention provides viral particles comprising arecombinant self-complementing genome (e.g., a self-complementary rAAVvector). AAV viral particles with self-complementing vector genomes andmethods of use of self-complementing AAV genomes are described in U.S.Pat. Nos. 6,596,535; 7,125,717; 7,465,583; 7,785,888; 7,790,154;7,846,729; 8,093,054; and 8,361,457; and Wang Z., et al., (2003) GeneTher 10:2105-2111, each of which are incorporated herein by reference inits entirety. A rAAV comprising a self-complementing genome will quicklyform a double stranded DNA molecule by virtue of its partiallycomplementing sequences (e.g., complementing coding and non-codingstrands of a heterologous nucleic acid). In some embodiments, the vectorcomprises first nucleic acid sequence encoding the heterologous nucleicacid and a second nucleic acid sequence encoding a complement of thenucleic acid, where the first nucleic acid sequence can form intrastrandbase pairs with the second nucleic acid sequence along most or all ofits length.

In some embodiments, the first heterologous nucleic acid sequenceencoding a RNAi and a second heterologous nucleic acid sequence encodingthe complement of the RNAi are linked by a mutated ITR (e.g., the rightITR). In some embodiments, the ITR comprises the polynucleotide sequence5′-CCACTCCCTCTCTGCGCGCTCGCTCGCTCACTGAGGCCGGGCGACCAAAGGTCGCCCGACGCCCGGGCTTTGCCCGGGCGGCCTCAGTGAGCGAGCGAGCGCGCAGAGA GGGA-3 (SEQ IDNO:15). The mutated ITR comprises a deletion of the D region comprisingthe terminal resolution sequence. As a result, on replicating an AAVviral genome, the rep proteins will not cleave the viral genome at themutated ITR and as such, a recombinant viral genome comprising thefollowing in 5′ to 3′ order will be packaged in a viral capsid: an AAVITR, the first heterologous polynucleotide sequence including regulatorysequences, the mutated AAV ITR, the second heterologous polynucleotidein reverse orientation to the first heterologous polynucleotide and athird AAV ITR.

VI. Viral Particles and Methods of Producing Viral Particles

The invention provides, inter alia, recombinant viral particlescomprising a nucleic acid encoding an RNAi of the present disclosure, aswell as methods of use thereof to treat a disease or disorder in amammal; e.g., Huntington's disease.

Viral Particles

The invention provides viral particles comprising the RNAi as disclosedherein. In some embodiments, the invention provides viral particles fordelivering the RNAi of the invention as disclosed herein. For example,the invention provides methods of using recombinant viral particles todeliver RNAi to treat a disease or disorder in a mammal; e.g., rAAVparticles comprising RNAi to treat HD. In some embodiments, therecombinant viral particle is a recombinant AAV particle. In someembodiments, the viral particle is a recombinant AAV particle comprisinga nucleic acid comprising a sequence an RNAi of the present disclosureflanked by one or two ITRs. The nucleic acid is encapsidated in the AAVparticle. The AAV particle also comprises capsid proteins. In someembodiments, the nucleic acid comprises the coding sequence(s) ofinterest (e.g., nucleic acid an RNAi of the present disclosure)operatively linked components in the direction of transcription, controlsequences including transcription initiation and termination sequences,thereby forming an expression cassette. The expression cassette isflanked on the 5′ and 3′ end by at least one functional AAV ITRsequences. By “functional AAV ITR sequences” it is meant that the ITRsequences function as intended for the rescue, replication and packagingof the AAV virion. See Davidson et al., PNAS, 2000, 97(7)3428-32;Passini et al., J. Virol., 2003, 77(12):7034-40; and Pechan et al., GeneTher., 2009, 16:10-16, all of which are incorporated herein in theirentirety by reference. For practicing some aspects of the invention, therecombinant vectors comprise at least all of the sequences of AAVessential for encapsidation and the physical structures for infection bythe rAAV. AAV ITRs for use in the vectors of the invention need not havea wild-type nucleotide sequence (e.g., as described in Kotin, Hum. GeneTher., 1994, 5:793-801), and may be altered by the insertion, deletionor substitution of nucleotides or the AAV ITRs may be derived from anyof several AAV serotypes. More than 40 serotypes of AAV are currentlyknown, and new serotypes and variants of existing serotypes continue tobe identified. See Gao et al., PNAS, 2002, 99(18): 11854-6; Gao et al.,PNAS, 2003, 100(10):6081-6; and Bossis et al., J. Virol., 2003,77(12):6799-810. Use of any AAV serotype is considered within the scopeof the present invention. In some embodiments, a rAAV vector is a vectorderived from an AAV serotype, including without limitation, AAV ITRs areAAV1, AAV2, AAV3, AAV4, AAV5, AAV6, AAV7, AAV8, AAVrh8, AAVrh8R, AAV9,AAV10, AAVrh10, AAV11, AAV12, AAV2R471A, AAV DJ, a goat AAV, bovine AAV,or mouse AAV capsid serotype ITRs or the like. In some embodiments, thenucleic acid in the AAV comprises an ITR of AAV1, AAV2, AAV3, AAV4,AAV5, AAV6, AAV7, AAV8, AAVrh8, AAVrh8R, AAV9, AAV10, AAVrh10, AAV11,AAV12, AAV2R471A, AAV DJ, a goat AAV, bovine AAV, or mouse AAV capsidserotype ITRs or the like. In some embodiments, the nucleic acid in theAAV further encodes an RNAi as described herein. For example, thenucleic acid in the AAV can comprise at least one ITR of any AAVserotype contemplated herein and can further encode an RNAi comprisingone strand that comprises a guide region and another strand thatcomprises a non-guide region. In one embodiment, the nucleic acid in theAAV can comprise at least one ITR of any AAV serotype and can furtherencode an RNAi comprising a first strand comprising a first nucleic acidcomprising the sequence 5′-UGGCCGUCCAUCUUGGACCCG-3′ (SEQ ID NO: 1) and asecond strand comprising a second nucleic acid comprising the sequence5′-CGGGUCCAAGAUGGACGGCCA-3′ (SEQ ID NO:2). In some embodiments, thenucleic acid in the AAV comprises 5′ to 3′ nucleic acid encoding thefollowing: an ITR (e.g., an AAV2 ITR), a promoter, a nucleic acidencoding an RNAi as disclosed herein, a polyadenylation signal, and anAAV ITR (e.g., an AAV2 ITR). In some embodiments, the nucleic acid inthe AAV comprises 5′ to 3′ nucleic acid encoding the following: an ITR(e.g., an AAV2 ITR), a promoter, a nucleic acid encoding an RNAicomprising a first strand comprising a first nucleic acid comprising thesequence 5′-UGGCCGUCCAUCUUGGACCCG-3′ (SEQ ID NO:1) and a second strandcomprising a second nucleic acid comprising the sequence5′-CGGGUCCAAGAUGGACGGCCA-3′ (SEQ ID NO:2), a polyadenylation signal, andan AAV ITR (e.g., an AAV2 ITR). In some embodiments, the nucleic acid inthe AAV comprises 5′ to 3′ nucleic acid encoding the following: an ITR(e.g., an AAV2 ITR), a CBA promoter, a nucleic acid encoding an RNAi asdisclosed herein, a polyadenylation signal (e.g., a bovine growthhormone polyA), and an AAV ITR (e.g., an AAV2 ITR). In some embodiments,the nucleic acid in the AAV comprises 5′ to 3′ nucleic acid encoding thefollowing: all or a functional portion of an ITR (e.g., an AAV2 ITR), aCBA promoter, an intron (e.g., a chimeric intron), a nucleic acidencoding an RNAi comprising a first strand comprising a first nucleicacid comprising the sequence 5′-UGGCCGUCCAUCUUGGACCCG-3′ (SEQ ID NO: 1),and a second strand comprising a second nucleic acid comprising thesequence 5′-CGGGUCCAAGAUGGACGGCCA-3′ (SEQ ID NO:2), a polyadenylationsignal (e.g., a bovine growth hormone polyA), and an AAV ITR (e.g., anAAV2 ITR). In some embodiments, the first strand and second strand forma duplex. In some embodiments, the first strand is linked to the secondstrand by a linker. In some embodiments, the linker comprises thenucleic acid sequence of SEQ ID NO:13.

In some embodiments, the nucleic acid in the AAV comprises 5′ to 3′nucleic acid encoding the following: an ITR (e.g., an AAV2 ITR), a CBApromoter, a nucleic acid encoding an RNAi comprising a first strandcomprising a first nucleic acid comprising the sequence5′-CGGGUCCAAGAUGGACGGCCA-3′ (SEQ ID NO:2), and a second strandcomprising a second nucleic acid comprising the sequence5′-UGGCCGUCCAUCUUGGACCCG-3′ (SEQ ID NO:1), a polyadenylation signal(e.g., a bovine growth hormone polyA), and an AAV ITR (e.g., an AAV2ITR). In some embodiments, the first strand and second strand form aduplex. In some embodiments, the first strand is linked to the secondstrand by a linker. In some embodiments, the linker comprises thenucleic acid sequence of SEQ ID NO: 13.

In another embodiment, the nucleic acid in the AAV can comprise at leastone ITR of any AAV serotype contemplated herein and can further encodean RNAi comprising a first strand comprising a first nucleic acidcomprising the sequence 5′-AGUCGGUGUGGUUGACAAGCA-3′ (SEQ ID NO:7) and asecond strand comprising a second nucleic acid comprising the sequence5′-UGCUUGUCAACCACACCGACU-3′ (SEQ ID NO:8). In some embodiments, thenucleic acid in the AAV comprises 5′ to 3′ nucleic acid encoding thefollowing: an ITR (e.g., an AAV2 ITR), a promoter, a nucleic acidencoding an RNAi as disclosed herein, a polyadenylation signal, and anAAV ITR (e.g., an AAV2 ITR). In some embodiments, the nucleic acid inthe AAV comprises 5′ to 3′ nucleic acid encoding the following: an ITR(e.g., an AAV2 ITR), a promoter, a nucleic acid encoding an RNAicomprising a first strand comprising a first nucleic acid comprising thesequence 5′-AGUCGGUGUGGUUGACAAGCA-3′ (SEQ ID NO:7) and a second strandcomprising a second nucleic acid comprising the sequence5′-UGCUUGUCAACCACACCGACU-3′ (SEQ ID NO:8), a polyadenylation signal, andan AAV ITR (e.g., an AAV2 ITR). In some embodiments, the nucleic acid inthe AAV comprises 5′ to 3′ nucleic acid encoding the following: an ITR(e.g., an AAV2 ITR), a CBA promoter, a chimeric intron, a nucleic acidencoding an RNAi as disclosed herein, a polyadenylation signal (e.g., abovine growth hormone polyA), and an AAV ITR (e.g., an AAV2 ITR). Insome embodiments, the nucleic acid in the AAV comprises 5′ to 3′ nucleicacid encoding the following: an ITR (e.g., an AAV2 ITR), a CBA promoter,a chimeric intron, a nucleic acid encoding an RNAi comprising a firststrand comprising a first nucleic acid comprising the sequence5′-AGUCGGUGUGGUUGACAAGCA-3′ (SEQ ID NO:7), and a second strandcomprising a second nucleic acid comprising the sequence5′-UGCUUGUCAACCACACCGACU-3′ (SEQ ID NO:8), a polyadenylation signal(e.g., a bovine growth hormone polyA), and an AAV ITR (e.g., an AAV2ITR). In some embodiments, the first strand and second strand form aduplex. In some embodiments, the first strand is linked to the secondstrand by a linker. In some embodiments, the linker comprises thenucleic acid sequence of SEQ ID NO: 13.

In another embodiment, the nucleic acid in the AAV can comprise at leastone ITR of any AAV serotype contemplated herein and can further encodean RNAi comprising a first strand comprising a first nucleic acidcomprising the sequence 5′-UGCUUGUCAACCACACCGACU-3′ (SEQ ID NO:8) and asecond strand comprising a second nucleic acid comprising the sequenceAGUCGGUGUGUGGUUGACAAGCA-3′ (SEQ ID NO:7). In some embodiments, thenucleic acid in the AAV comprises 5′ to 3′ nucleic acid encoding thefollowing: an ITR (e.g., an AAV2 ITR), a promoter, a nucleic acidencoding an RNAi as disclosed herein, a polyadenylation signal, and anAAV ITR (e.g., an AAV2 ITR). In some embodiments, the nucleic acid inthe AAV comprises 5′ to 3′ nucleic acid encoding the following: an ITR(e.g., an AAV2 ITR), a promoter, an intron, a nucleic acid encoding anRNAi comprising a first strand comprising a first nucleic acidcomprising the sequence 5′-UGCUUGUCAACCACACCGACU-3′ (SEQ ID NO:8) and asecond strand comprising a second nucleic acid comprising the sequence5′-AGUCGGUGUGGUUGACAAGCA-3′ (SEQ ID NO:7), a polyadenylation signal, andan AAV ITR (e.g., an AAV2 ITR). In some embodiments, the nucleic acid inthe AAV comprises 5′ to 3′ nucleic acid encoding the following: an ITR(e.g., an AAV2 ITR), a CBA promoter, a nucleic acid encoding an RNAi asdisclosed herein, a polyadenylation signal (e.g., a bovine growthhormone polyA), and an AAV ITR (e.g., an AAV2 ITR). In some embodiments,the nucleic acid in the AAV comprises 5′ to 3′ nucleic acid encoding thefollowing: an ITR (e.g., an AAV2 ITR), a CBA promoter, an intron, anucleic acid encoding an RNAi comprising a first strand comprising afirst nucleic acid comprising the sequence 5′-UGCUUGUCAACCACACCGACU-3′,and a second strand comprising a second nucleic acid comprising thesequence 5′-AGUCGGUGUGGUUGACAAGCA-3′ (SEQ ID NO:7), a polyadenylationsignal (e.g., a bovine growth hormone polyA), and an AAV ITR (e.g., anAAV2 ITR). In some embodiments, the first strand and second strand forma duplex. In some embodiments, the first strand is linked to the secondstrand by a linker. In some embodiments, the linker comprises thenucleic acid sequence of SEQ ID NO: 13.

In some embodiments, a vector may include a (one or more) stuffernucleic acid. In some embodiments, the stuffer nucleic acid may comprisea sequence that encodes a reporter polypeptide. As will be appreciatedby those of skill in the art, the stuffer nucleic acid may be located ina variety of regions within the vector, and may be comprised of acontinuous sequence (e.g., a single stuffer nucleic acid in a singlelocation) or multiple sequences (e.g., more than one stuffer nucleicacid in more than one location (e.g., 2 locations, 3 locations, etc.)within the vector. In some embodiments, the stuffer nucleic acid may belocated downstream of the RNAi sequence. In embodiments, the stuffernucleic acid may be located upstream of the RNAi sequence (e.g., betweenthe promoter and the nucleic acid encoding the RNAi). As will also beappreciated by those of skill in the art a variety of nucleic acids maybe used as a stuffer nucleic acid. In some embodiments, the stuffernucleic acid comprises all or a portion of a human alpha-1-antitrypsin(AAT) stuffer sequence or a C16 P1 chromosome 16 P1 clone (human C16)stuffer sequence. In some embodiments, the stuffer sequence comprisesall or a portion of a gene. For example, the stuffer sequence comprisesa portion of the human AAT sequence. One skilled in the art wouldrecognize that different portions of a gene (e.g., the human AATsequence) can be used as a stuffer fragment. For example, the stufferfragment may be from the 5′ end of the gene, the 3′ end of the gene, themiddle of a gene, a non-coding portion of the gene (e.g., an intron), acoding region of the gene (e.g. an exon), or a mixture of non-coding andcoding portions of a gene. One skilled in the art would also recognizethat all or a portion of stuffer sequence may be used as a stuffersequence. In some embodiments, the stuffer sequence comprises thenucleotide sequence of SEQ ID NO: 18.

In further embodiments, the rAAV particle comprises capsid proteins ofAAV1, AAV2, AAV3, AAV4, AAV5, AA6, AAV7, AAV8, AAV9, AAVrh.8, AAVrh8R,AAVrh.10, AAV11, AAV12, or mutants of these capsid proteins. In someembodiments, a mutant capsid protein maintains the ability to form anAAV capsid. In some embodiments, the rAAV particle comprises AAV5tyrosine mutant capsid (Zhong L. et al., (2008) Proc Natl Acad Sci USA105(22):7827-7832. In further embodiments, the rAAV particle comprisescapsid proteins of an AAV serotype from Clades A-F (Gao, et al., J.Virol. 2004, 78(12):6381).

Different AAV serotypes are used to optimize transduction of particulartarget cells or to target specific cell types within a particular targettissue (e.g., a diseased tissue). A rAAV particle can comprise viralproteins and viral nucleic acids of the same serotype or a mixedserotype. For example, in some embodiments a rAAV particle can compriseAAV1 capsid proteins and at least one AAV2 ITR or it can comprise AAV2capsid proteins and at least one AAV1 ITR. Any combination of AAVserotypes for production of a rAAV particle is provided herein as ifeach combination had been expressly stated herein. In some embodiments,the invention provides rAAV particles comprising an AAV1 capsid and arAAV vector of the present disclosure (e.g., an expression cassettecomprising nucleic acid encoding an RNAi of the present disclosure),flanked by at least one AAV2 ITR. In some embodiments, the inventionprovides rAAV particles comprising an AAV2 capsid.

In some aspects, the invention provides viral particles comprising arecombinant self-complementing genome. AAV viral particles withself-complementing genomes and methods of use of self-complementing AAVgenomes are described in U.S. Pat. Nos. 6,596,535; 7,125,717; 7,465,583;7,785,888; 7,790,154; 7,846,729; 8,093,054; and 8,361,457; and Wang Z.,et al., (2003) Gene Ther 10:2105-2111, each of which are incorporatedherein by reference in its entirety. A rAAV comprising aself-complementing genome will quickly form a double stranded DNAmolecule by virtue of its partially complementing sequences (e.g.,complementing coding and non-coding strands of a transgene). In someembodiments, the invention provides an AAV viral particle comprising anAAV genome, wherein the rAAV genome comprises a first heterologouspolynucleotide sequence (e.g., an RNAi of the present disclosure) and asecond heterologous polynucleotide sequence (e.g., antisense strand ofan RNAi of the present disclosure) wherein the first heterologouspolynucleotide sequence can form intrastrand base pairs with the secondpolynucleotide sequence along most or all of its length. In someembodiments, the first heterologous polynucleotide sequence and a secondheterologous polynucleotide sequence are linked by a sequence thatfacilitates intrastrand basepairing; e.g., a hairpin DNA structure.Hairpin structures are known in the art, for example in miRNA or siRNAmolecules. In some embodiments, the first heterologous polynucleotidesequence and a second heterologous polynucleotide sequence are linked bya mutated ITR (e.g., the right ITR). In some embodiments, the ITRcomprises the polynucleotide sequence5′-CCACTCCCTCTCTGCGCGCTCGCTCGCTCACTGAGGCCGGGCGACCAAAGGTCGCCCGACGCCCGGGCTTTGCCCGGGCGGCCTCAGTGAGCGAGCGAGCGCGCAGA GAGGGA-3 (SEQ IDNO: 15). The mutated ITR comprises a deletion of the D region comprisingthe terminal resolution sequence. As a result, on replicating an AAVviral genome, the rep proteins will not cleave the viral genome at themutated ITR and as such, a recombinant viral genome comprising thefollowing in 5′ to 3′ order will be packaged in a viral capsid: an AAVITR, the first heterologous polynucleotide sequence including regulatorysequences, the mutated AAV ITR, the second heterologous polynucleotidein reverse orientation to the first heterologous polynucleotide and athird AAV ITR. In some embodiments, the invention provides AAV viralparticles comprising a recombinant viral genome comprising a functionalAAV2 ITR, a first polynucleotide sequence encoding an RNAi of thepresent disclosure, a mutated AAV2 ITR comprising a deletion of the Dregion and lacking a functional terminal resolution sequence, a secondpolynucleotide sequence comprising the complementary sequence to thesequence encoding an RNAi of the present disclosure, of the firstpolynucleotide sequence and a functional AAV2 ITR.

In some embodiments, the viral particle is an adenoviral particle. Insome embodiments, the adenoviral particle is a recombinant adenoviralparticle. e.g., a polynucleotide vector comprising an RNAi of thepresent disclosure between two ITRs. In some embodiments, the adenoviralparticle lacks or contains a defective copy of one or more E1 genes,which renders the adenovirus replication-defective. Adenoviruses includea linear, double-stranded DNA genome within a large (˜950 Å),non-enveloped icosahedral capsid. Adenoviruses have a large genome thatcan incorporate more than 30 kb of heterologous sequence (e.g., in placeof the E1 and/or E3 region), making them uniquely suited for use withlarger heterologous genes. They are also known to infect dividing andnon-dividing cells and do not naturally integrate into the host genome(although hybrid variants may possess this ability). In someembodiments, the adenoviral vector may be a first generation adenoviralvector with a heterologous sequence in place of E1. In some embodiments,the adenoviral vector may be a second generation adenoviral vector withadditional mutations or deletions in E2A, E2B, and/or E4. In someembodiments, the adenoviral vector may be a third generation or guttedadenoviral vector that lacks all viral coding genes, retaining only theITRs and packaging signal and requiring a helper adenovirus in trans forreplication, and packaging. Adenoviral particles have been investigatedfor use as vectors for transient transfection of mammalian cells as wellas gene therapy vectors. For further description, see, e.g., Danthinne,X. and Imperiale, M. J. (2000) Gene Ther. 7:1707-14 and Tatsis, N. andErtl, H. C. (2004) Mol. Ther. 10:616-29.

In some embodiments, the viral particle is a recombinant adenoviralparticle comprising a nucleic acid encoding an RNAi of the presentdisclosure. Use of any adenovirus serotype is considered within thescope of the present invention. In some embodiments, the recombinantadenoviral vector is a vector derived from an adenovirus serotype,including without limitation, AdHu2, AdHu 3, AdHu4, AdHu5, AdHu7,AdHu11, AdHu24, AdHu26, AdHu34, AdHu35, AdHu36, AdHu37, AdHu41, AdHu48,AdHu49, AdHu50, AdC6, AdC7, AdC69, bovine Ad type 3, canine Ad type 2,ovine Ad. and porcine Ad type 3. The adenoviral particle also comprisescapsid proteins. In some embodiments, the recombinant viral particlescomprise an adenoviral particle in combination with one or more foreignviral capsid proteins. Such combinations may be referred to aspseudotyped recombinant adenoviral particles. In some embodiments,foreign viral capsid proteins used in pseudotyped recombinant adenoviralparticles are derived from a foreign virus or from another adenovirusserotype. In some embodiments, the foreign viral capsid proteins arederived from, including without limitation, reovirus type 3. Examples ofvector and capsid protein combinations used in pseudotyped adenovirusparticles can be found in the following references (Tatsis, N. et al.(2004) Mol. Ther. 10(4):616-629 and Ahi, Y. et al. (2011) Curr. GeneTher. 11(4):307-320). Different adenovirus serotypes can be used tooptimize transduction of particular target cells or to target specificcell types within a particular target tissue (e.g., a diseased tissue).Tissues or cells targeted by specific adenovirus serotypes, includewithout limitation, lung (e.g. HuAd3), spleen and liver (e.g. HuAd37),smooth muscle, synoviocytes, dendritic cells, cardiovascular cells,tumor cell lines (e.g. HuAd11), and dendritic cells (e.g. HuAd5pseudotyped with reovirus type 3, HuAd30, or HuAd35). For furtherdescription, see Ahi, Y. et al. (2011) Curr. Gene Ther. 11(4):307-320,Kay, M. et al. (2001) Nat. Med 7(1):33-40, and Tatsis, N. et al. (2004)Mol. Ther. 10(4):616-629. Adenoviral vectors have been administered byintrastriatal administration (see, e.g., Mittoux, V. et al. (2002) J.Neurosci. 22:4478-86).

In some embodiments, the viral particle is a lentiviral particle. Insome embodiments, the lentiviral particle is a recombinant lentiviralparticle, e.g., a polynucleotide vector encoding an RNAi of the presentdisclosure between two LTRs. Lentiviruses are positive-sense, ssRNAretroviruses with a genome of approximately 10 kb. Lentiviruses areknown to integrate into the genome of dividing and non-dividing cells.Lentiviral particles may be produced, for example, by transfectingmultiple plasmids (typically the lentiviral genome and the genesrequired for replication and/or packaging are separated to prevent viralreplication) into a packaging cell line, which packages the modifiedlentiviral genome into lentiviral particles. In some embodiments, alentiviral particle may refer to a first generation vector that lacksthe envelope protein. In some embodiments, a lentiviral particle mayrefer to a second generation vector that lacks all genes except thegag/pol and tat/rev regions. In some embodiments, a lentiviral particlemay refer to a third generation vector that only contains the endogenousrev, gag, and pol genes and has a chimeric LTR for transduction withoutthe tat gene (see Dull, T. et al. (1998) J. Virol. 72:8463-71). Forfurther description, see Durand, S. and Cimarelli, A. (2011) Viruses3:132-59.

In some embodiments, the viral particle is a recombinant lentiviralparticle comprising a nucleic acid encoding an RNAi of the presentdisclosure. Use of any lentiviral vector is considered within the scopeof the present invention. In some embodiments, the lentiviral vector isderived from a lentivirus including, without limitation, humanimmunodeficiency virus-1 (HIV-1), human immunodeficiency virus-2(HIV-2), simian immunodeficiency virus (SIV), feline immunodeficiencyvirus (FIV), equine infectious anemia virus (EIAV), bovineimmunodeficiency virus (BIV), Jembrana disease virus (JDV), visna virus(VV), and caprine arthritis encephalitis virus (CAEV). The lentiviralparticle also comprises capsid proteins. In some embodiments, therecombinant viral particles comprise a lentivirus vector in combinationwith one or more foreign viral capsid proteins. Such combinations may bereferred to as pseudotyped recombinant lentiviral particles. In someembodiments, foreign viral capsid proteins used in pseudotypedrecombinant lentiviral particles are derived from a foreign virus. Insome embodiments, the foreign viral capsid protein used in pseudotypedrecombinant lentiviral particles is Vesicular stomatitis virusglycoprotein (VSV-GP). VSV-GP interacts with a ubiquitous cell receptor,providing broad tissue tropism to pseudotyped recombinant lentiviralparticles. In addition, VSV-GP is thought to provide higher stability topseudotyped recombinant lentiviral particles. In other embodiments, theforeign viral capsid proteins are derived from, including withoutlimitation, Chandipura virus, Rabies virus, Mokola virus, Lymphocyticchoriomeningitis virus (LCMV), Ross River virus (RRV), Sindbis virus,Semliki Forest virus (SFV), Venezuelan equine encephalitis virus, Ebolavirus Reston, Ebola virus Zaire, Marburg virus, Lassa virus, Avianleukosis virus (ALV), Jaagsiekte sheep retrovirus (JSRV), Moloney Murineleukemia virus (MLV), Gibbon ape leukemia virus (GALV), Felineendogenous retrovirus (RD114), Human T-lymphotrophic virus 1 (HTLV-1),Human foamy virus, Maedi-visna virus (MVV), SARS-CoV, Sendai virus,Respiratory syncytia virus (RSV), Human parainfluenza virus type 3,Hepatitis C virus (HCV), Influenza virus, Fowl plague virus (FPV), orAutographa californica multiple nucleopolyhedro virus (AcMNPV). Examplesof vector and capsid protein combinations used in pseudotyped Lentivirusparticles can be found, for example, in Cronin, J. et al. (2005). Curr.Gene Ther. 5(4):387-398. Different pseudotyped recombinant lentiviralparticles can be used to optimize transduction of particular targetcells or to target specific cell types within a particular target tissue(e.g., a diseased tissue). For example, tissues targeted by specificpseudotyped recombinant lentiviral particles, include withoutlimitation, liver (e.g. pseudotyped with a VSV-G, LCMV, RRV, or SeV Fprotein), lung (e.g. pseudotyped with an Ebola, Marburg, SeV F and HN,or JSRV protein), pancreatic islet cells (e.g. pseudotyped with an LCMVprotein), central nervous system (e.g. pseudotyped with a VSV-G, LCMV,Rabies, or Mokola protein), retina (e.g. pseudotyped with a VSV-G orMokola protein), monocytes or muscle (e.g. pseudotyped with a Mokola orEbola protein), hematopoietic system (e.g. pseudotyped with an RD114 orGALV protein), or cancer cells (e.g. pseudotyped with a GALV or LCMVprotein). For further description, see Cronin, J. et al. (2005). Curr.Gene Ther. 5(4):387-398 and Kay, M. et al. (2001) Nat. Med. 7(1):33-40.

In some embodiments, the viral particle is a herpes simplex virus (HSV)particle. In some embodiments, the HSV particle is a rHSV particle,e.g., a polynucleotide vector encoding an RNAi of the present disclosurebetween two TRs. HSV is an enveloped, double-stranded DNA virus with agenome of approximately 152 kb. Advantageously, approximately half ofits genes are nonessential and may be deleted to accommodateheterologous sequence. HSV particles infect non-dividing cells. Inaddition, they naturally establish latency in neurons, travel byretrograde transport, and can be transferred across synapses, makingthem advantageous for transfection of neurons and/or gene therapyapproaches involving the nervous system. In some embodiments, the HSVparticle may be replication-defective or replication-competent (e.g.,competent for a single replication cycle through inactivation of one ormore late genes). For further description, see Manservigi, R. et al.(2010) Open Virol. J. 4:123-56.

In some embodiments, the viral particle is a rHSV particle comprising anucleic acid encoding an RNAi of the present disclosure. Use of any HSVvector is considered within the scope of the present invention. In someembodiments, the HSV vector is derived from a HSV serotype, includingwithout limitation, HSV-1 and HSV-2. The HSV particle also comprisescapsid proteins. In some embodiments, the recombinant viral particlescomprise a HSV vector in combination with one or more foreign viralcapsid proteins. Such combinations may be referred to as pseudotypedrHSV particles. In some embodiments, foreign viral capsid proteins usedin pseudotyped rHSV particles are derived from a foreign virus or fromanother HSV serotype. In some embodiments, the foreign viral capsidprotein used in a pseudotyped rHSV particle is a Vesicular stomatitisvirus glycoprotein (VSV-GP). VSV-GP interacts with a ubiquitous cellreceptor, providing broad tissue tropism to pseudotyped rHSV particles.In addition, VSV-GP is thought to provide higher stability topseudotyped rHSV particles. In other embodiments, the foreign viralcapsid protein may be from a different HSV serotype. For example, anHSV-1 vector may contain one or more HSV-2 capsid proteins. DifferentHSV serotypes can be used to optimize transduction of particular targetcells or to target specific cell types within a particular target tissue(e.g., a diseased tissue). Tissues or cells targeted by specificadenovirus serotypes include without limitation, central nervous systemand neurons (e.g. HSV-1). For further description, see Manservigi, R. etal. (2010) Open Virol J 4:123-156, Kay, M. et al. (2001) Nat. Med.7(1):33-40, and Meignier, B. et al. (1987) J. Infect. Dis.155(5):921-930.

Production of Viral Particles

rAAV particles can be produced using methods known in the art. See,e.g., U.S. Pat. Nos. 6,566,118; 6,989,264; and 6,995,006. In practicingthe invention, host cells for producing rAAV particles include mammaliancells, insect cells, plant cells, microorganisms and yeast. Host cellscan also be packaging cells in which the AAV rep and cap genes arestably maintained in the host cell or producer cells in which the AAVvector genome is stably maintained. Exemplary packaging and producercells are derived from 293, A549 or HeLa cells. AAV vectors are purifiedand formulated using standard techniques known in the art.

Methods known in the art for production of rAAV vectors include but arenot limited to transfection, stable cell line production, and infectioushybrid virus production systems which include adenovirus-AAV hybrids,herpesvirus-AAV hybrids (Conway, J E et al., (1997) J. Virology71(11):8780-8789) and baculovirus-AAV hybrids, rAAV production culturesfor the production of rAAV virus particles all require; 1) suitable hostcells, including, for example, human-derived cell lines such as HeLa,A549, or 293 cells, or insect-derived cell lines such as SF-9, in thecase of baculovirus production systems; 2) suitable helper virusfunction, provided by wild-type or mutant adenovirus (such astemperature sensitive adenovirus), herpes virus, baculovirus, or aplasmid construct providing helper functions; 3) AAV rep and cap genesand gene products; 4) a nucleic acid (such as a therapeutic nucleicacid) flanked by at least one AAV ITR sequences: and 5) suitable mediaand media components to support rAAV production. In some embodiments,the AAV rep and cap gene products may be from any AAV serotype. Ingeneral, but not obligatory, the AAV rep gene product is of the sameserotype as the ITRs of the rAAV vector genome as long as the rep geneproducts may function to replicated and package the rAAV genome.Suitable media known in the art may be used for the production of rAAVvectors. These media include, without limitation, media produced byHyclone Laboratories and JRH including Modified Eagle Medium (MEM),Dulbecco's Modified Eagle Medium (DMEM), custom formulations such asthose described in U.S. Pat. No. 6,566,118, and Sf-900 II SFM media asdescribed in U.S. Pat. No. 6,723,551, each of which is incorporatedherein by reference in its entirety, particularly with respect to custommedia formulations for use in production of recombinant AAV vectors. Insome embodiments, the AAV helper functions are provided by adenovirus orHSV. In some embodiments, the AAV helper functions are provided bybaculovirus and the host cell is an insect cell (e.g., Spodopterafrugiperda (Sf9) cells).

In some embodiments, rAAV particles may be produced by a tripletransfection method, such as the exemplary triple transfection methodprovided infra. Briefly, a plasmid containing a rep gene and a capsidgene, along with a helper adenoviral plasmid, may be transfected (e.g.,using the calcium phosphate method) into a cell line (e.g., HEK-293cells), and virus may be collected and optionally purified. As such, insome embodiments, the rAAV particle was produced by triple transfectionof a nucleic acid encoding the rAAV vector, a nucleic acid encoding AAVrep and cap, and a nucleic acid encoding AAV helper virus functions intoa host cell, wherein the transfection of the nucleic acids to the hostcells generates a host cell capable of producing rAAV particles.

In some embodiments, rAAV particles may be produced by a producer cellline method, such as the exemplary producer cell line method providedinfra (see also (referenced in Martin et al., (2013) Human Gene TherapyMethods 24:253-269). Briefly, a cell line (e.g., a HeLa cell line) maybe stably transfected with a plasmid containing a rep gene, a capsidgene, and a promoter-heterologous nucleic acid sequence. Cell lines maybe screened to select a lead clone for rAAV production, which may thenbe expanded to a production bioreactor and infected with an adenovirus(e.g., a wild-type adenovirus) as helper to initiate rAAV production.Virus may subsequently be harvested, adenovirus may be inactivated(e.g., by heat) and/or removed, and the rAAV particles may be purified.As such, in some embodiments, the rAAV particle was produced by aproducer cell line comprising one or more of nucleic acid encoding therAAV vector, a nucleic acid encoding AAV rep and cap, and a nucleic acidencoding AAV helper virus functions.

In some aspects, a method is provided for producing any rAAV particle asdisclosed herein comprising (a) culturing a host cell under a conditionthat rAAV particles are produced, wherein the host cell comprises (i)one or more AAV package genes, wherein each said AAV packaging geneencodes an AAV replication and/or encapsidation protein; (ii) an rAAVpro-vector comprising a nucleic acid encoding an RNAi of the presentdisclosure as described herein flanked by at least one AAV ITR, and(iii) an AAV helper function; and (b) recovering the rAAV particlesproduced by the host cell. In some embodiments, the RNAi comprises thenucleotide sequence of SEQ ID NO:7. In some embodiments, said at leastone AAV ITR is selected from the group consisting of AAV ITRs are AAV1,AAV2, AAV3, AAV4, AAV5, AAV6, AAV7, AAV8, AAVrh8, AAVrh8R, AAV9, AAV10,AAVrh10, AAV11, AAV12, AAV2R471A, AAV DJ, a goat AAV, bovine AAV, ormouse AAV capsid serotype ITRs or the like. In some embodiments, saidencapsidation protein is selected from the group consisting of AAV1,AAV2, AAV3, AAV4, AAV5, AAV6 (e.g., a wild-type AAV6 capsid, or avariant AAV6 capsid such as ShH10, as described in U.S. PG Pub.2012/0164106), AAV7, AAV8, AAVrh8, AAVrh8R, AAV9 (e.g., a wild-type AAV9capsid, or a modified AAV9 capsid as described in U.S. PG Pub.2013/0323226), AAV10, AAVrh10, AAV11, AAV12, a tyrosine capsid mutant, aheparin binding capsid mutant, an AAV2R471A capsid, an AAVAAV2/2-7m8capsid, an AAV DJ capsid (e.g., an AAV-DJ/8 capsid, an AAV-DJ/9 capsid,or any other of the capsids described in U.S. PG Pub. 2012/0066783),AAV2 N587A capsid, AAV2 E548A capsid, AAV2 N708A capsid, AAV V708Kcapsid, goat AAV capsid, AAV1/AAV2 chimeric capsid, bovine AAV capsid,mouse AAV capsid, rAAV2/HBoV1 capsid, or an AAV capsid described in U.S.Pat. No. 8,283,151 or International Publication No. WO/2003/042397. Insome embodiments, a mutant capsid protein maintains the ability to forman AAV capsid. In some embodiments, the encapsidation protein is an AAV5tyrosine mutant capsid protein. In further embodiments, the rAAVparticle comprises capsid proteins of an AAV serotype from Clades A-F.In some embodiments, the rAAV particles comprise an AAV1 capsid and arecombinant genome comprising AAV2 ITRs, a mutant AAV2 ITR and nucleicacid encoding an RNAi of the present disclosure. In a furtherembodiment, the rAAV particles are purified. The term “purified” as usedherein includes a preparation of rAAV particles devoid of at least someof the other components that may also be present where the rAAVparticles naturally occur or are initially prepared from. Thus, forexample, isolated rAAV particles may be prepared using a purificationtechnique to enrich it from a source mixture, such as a culture lysateor production culture supernatant. Enrichment can be measured in avariety of ways, such as, for example, by the proportion ofDNase-resistant particles (DRPs) or genome copies (gc) present in asolution, or by infectivity, or it can be measured in relation to asecond, potentially interfering substance present in the source mixture,such as contaminants, including production culture contaminants orin-process contaminants, including helper virus, media components, andthe like.

Numerous methods are known in the art for production of adenoviralvector particles. For example, for a gutted adenoviral vector, theadenoviral vector genome and a helper adenovirus genome may betransfected into a packaging cell line (e.g., a 293 cell line). In someembodiments, the helper adenovirus genome may contain recombinationsites flanking its packaging signal, and both genomes may be transfectedinto a packaging cell line that expresses a recombinase (e.g., theCre/loxP system may be used), such that the adenoviral vector ofinterest is packaged more efficiently than the helper adenovirus (see,e.g., Alba, R. et al. (2005) Gene Ther. 12 Suppl 1:S18-27). Adenoviralvectors may be harvested and purified using standard methods, such asthose described herein.

Numerous methods are known in the art for production of lentiviralvector particles. For example, for a third-generation lentiviral vector,a vector containing the lentiviral genome of interest with gag and polgenes may be co-transfected into a packaging cell line (e.g., a 293 cellline) along with a vector containing a rev gene. The lentiviral genomeof interest also contains a chimeric LTR that promotes transcription inthe absence of Tat (see Dull, T. et al. (1998) J. Virol. 72:8463-71).Lentiviral vectors may be harvested and purified using methods (e.g.,Segura M M, et al., (2013) Expert Opin Biol Ther. 13(7):987-1011)described herein.

Numerous methods are known in the art for production of HSV particles.HSV vectors may be harvested and purified using standard methods, suchas those described herein. For example, for a replication-defective HSVvector, an HSV genome of interest that lacks all of the immediate early(IE) genes may be transfected into a complementing cell line thatprovides genes required for virus production, such as ICP4, ICP27, andICP0 (see, e.g., Samaniego, L. A. et al. (1998) J. Virol. 72:3307-20).HSV vectors may be harvested and purified using methods described (e.g.,Goins, W F et al., (2014) Herpes Simplex Virus Methods in MolecularBiology 1144:63-79).

Also provided herein are pharmaceutical compositions comprising arecombinant viral particle comprising a transgene encoding an RNAi ofthe present disclosure and a pharmaceutically acceptable carrier. Thepharmaceutical compositions may be suitable for any mode ofadministration described herein. A pharmaceutical composition of arecombinant viral particle comprising a nucleic acid encoding an RNAi ofthe present disclosure can be introduced to the brain. For example, arecombinant viral particle comprising a nucleic acid encoding an RNAi ofthe present disclosure can be administered intrastriatally. Any of therecombinant viral particles of the present disclosure may be used,including rAAV, adenoviral, lentiviral, and HSV particles.

In some embodiments, the pharmaceutical compositions comprising arecombinant viral particle comprising a transgene encoding an RNAi ofthe present disclosure described herein and a pharmaceuticallyacceptable carrier is suitable for administration to human. Suchcarriers are well known in the art (see, e.g., Remington'sPharmaceutical Sciences, 15th Edition, pp. 1035-1038 and 1570-1580). Insome embodiments, the pharmaceutical compositions comprising a rAAVdescribed herein and a pharmaceutically acceptable carrier is suitablefor injection into the brain of a mammal (e.g., intrastriataladministration). In some embodiments, the pharmaceutical compositionscomprising a recombinant lentiviral particle described herein and apharmaceutically acceptable carrier is suitable for injection into thebrain of a mammal (e.g., intrastriatal administration). In someembodiments, the pharmaceutical compositions comprising a recombinantadenoviral particle described herein and a pharmaceutically acceptablecarrier is suitable for injection into the brain of a mammal (e.g.,intrastriatal administration). In some embodiments, the pharmaceuticalcompositions comprising a recombinant HSV particle described herein anda pharmaceutically acceptable carrier is suitable for injection into thebrain of a mammal (e.g., intrastriatal administration).

Such pharmaceutically acceptable carriers can be sterile liquids, suchas water and oil, including those of petroleum, animal, vegetable orsynthetic origin, such as peanut oil, soybean oil, mineral oil, and thelike. Saline solutions and aqueous dextrose, polyethylene glycol (PEG)and glycerol solutions can also be employed as liquid carriers,particularly for injectable solutions. The pharmaceutical compositionmay further comprise additional ingredients, for example preservatives,buffers, tonicity agents, antioxidants and stabilizers, nonionic wettingor clarifying agents, viscosity-increasing agents, and the like. Thepharmaceutical compositions described herein can be packaged in singleunit dosages or in multidosage forms. The compositions are generallyformulated as sterile and substantially isotonic solution.

VII. Articles of Manufacture and Kits

Also provided are kits or articles of manufacture for use in the methodsdescribed herein. In aspects, the kits comprise the compositionsdescribed herein (e.g., a recombinant viral particle of the presentdisclosure, such as a rAAV particle comprising nucleic acid encoding anRNAi of the present disclosure) in suitable packaging. Suitablepackaging for compositions (such as intrastriatal compositions)described herein are known in the art, and include, for example, vials(such as sealed vials), vessels, ampules, bottles, jars, flexiblepackaging (e.g., sealed Mylar or plastic bags), and the like. Thesearticles of manufacture may further be sterilized and/or sealed.

The present invention also provides kits comprising compositionsdescribed herein and may further comprise instruction(s) on methods ofusing the composition, such as uses described herein. The kits describedherein may further include other materials desirable from a commercialand user standpoint, including other buffers, diluents, filters,needles, syringes, and package inserts with instructions for performingany methods described herein. For example, in some embodiments, the kitcomprises a composition of recombinant viral particles comprising atransgene encoding an RNAi of the present disclosure for delivery of atleast 1×10⁹ genome copies into the brain of a mammal (e.g., throughintrastriatal administration) to a primate as described herein, apharmaceutically acceptable carrier suitable for injection into thebrain of a primate, and one or more of: a buffer, a diluent, a filter, aneedle, a syringe, and a package insert with instructions for performinginjections into the brain of a primate (e.g., intrastriataladministration). In some embodiments, the kit comprising instructionsfor treating Huntington's disease with the recombinant viral particlesdescribed herein. In some embodiments, the kit comprising instructionsfor using the recombinant viral particles described herein according toany one of the methods described herein.

EXAMPLES

The invention will be more fully understood by reference to thefollowing examples. They should not, however, be construed as limitingthe scope of the invention. It is understood that the examples andembodiments described herein are for illustrative purposes only and thatvarious modifications or changes in light thereof will be suggested topersons skilled in the art and are to be included within the spirit andpurview of this application and scope of the appended claims.

Example 1: AAV2/1-miRNA-Htt Reduces Htt Expression In Vitro

RNA interference (RNAi) provides an approach for the treatment of manyhuman diseases. However, the safety of RNAi-based therapies can behampered by the ability of small inhibitory RNAs (siRNAs) to bind tounintended mRNAs and reduce their expression, an effect known asoff-target gene silencing. Off-targeting primarily occurs when the seedregion (nucleotides 2-8 of the small RNA) pairs with sequences in3′-UTRs of unintended mRNAs and directs translational repression anddestabilization of those transcripts. To date, most therapeutic RNAisequences are selected primarily for gene silencing efficacy, and laterevaluated for safety. Two siRNAs were generated to treat Huntington'sdisease (HD), a dominant neurodegenerative disorder, with minimaloff-targeting potential (i.e., those with a scarcity of seed complementswithin all known human and rhesus monkey 3′-UTRs) which demonstratespotent huntingtin silencing in the mouse brain with a low in silicooff-target profile (Table 1, FIG. 1A). One sequence (207) was tested forits ability to rescue behavioral phenotypes in the YAC128 mouse model ofHD. Striatal delivery of AAV2/1-miRNA-Htt-207 not only reduces Htt mRNAand protein levels in the brain, but also corrects the aberrantbehavioral profiles in YAC128 mice and demonstrates high guide strandactivity and precise 5′ processing, minimizing the potential for offtarget effects.

TABLE 1 miRNA and reverse complement (target) sequencesfor 206 and 207 as well as the top and bottomsequences for cloning, including restriction site overhangs. miRNA SEQID Component Sequence ID NO: 206 miRNA sequence uGGCCGUCCAUCUUGGACCCG  1(anti-sense, 5′→3′) 206 reverse complement CGGGUCCAAGAUGGACGGCCa  2(sense, 5′→3′) 206 DNA sequence encoding GTGGCCGTCCATCTTGGACC  3miRNA duplex CGGTTTTGGCCACTGACTGA CCGGGTCCAATGGACGGCCA 206RNA sequence of miRNA GUGGCCGUCCAUCUUGGACC  4 duplexCGGUUUUGGCCACUGACUGA CCGGGUCCAAUGGACGGCCA 206 top sequence for TGCTGTGGCCGTCCATCTTG  5 cloning (5′→3′) stem GACCCGGTTTTGGCCACTGAloop that contains CTGAC

AATGGACG the actual miRNA GCCA sequence, including restriction siteoverhangs for  cloning* 206 bottom sequence for CCTG TGGCCGTCCAT

 6 cloning (5′→3′)

GTCAGTCAGTGGCCAAA reverse complement of ACCGGGTCCAAGATGGACGGsequence in column to CCA C the left, including restriction siteoverhangs for cloning* 207 miRNA sequence AGUCGGUGUGGUUGACAAGCA  7(anti-sense, 5′→3′) 207 reverse complement UGCUUGUCAACCACACCGACU   8(sense, 5′→3′) 207 DNA sequence encoding AGTCGGTGTGGTTGACAAGCA  9miRNA duplex GTTTTGGCCACTGACTGACTG CTTGTCCCACACCGACT 207RNA sequence of miRNA AGUCGGUGUGGUUGACAAGCA 10 duplexGUUUUGGCCACUGACUGACUG CUUGUCCCACACCGACU 207 top sequence for TGCTGAGTCGGTGTGGTTGA 11 cloning (5′→3′) stem CAAGCAGTTTTGGCCACTGAloop that contains the CTGAC

CCACACC actual miRNA sequence, GACT including restrictionsite overhangs for cloning* 207 bottom sequence for CCTG AGTCGGTGTGG

12 cloning (5′→3′)

GTCAGTCAGTGGCCAAA reverse complement of ACTGCTTGTCAACCACACCGsequence in column to ACT C the left, including restriction siteoverhangs for cloning* *For sequences for cloning-Restriction siteoverhangs for cloning are underlined; miRNA sequences in bold; loopsequence in plain text; bases 1-8 of miRNA reverse complement in bold,italics: bases 11-21 (11-20 for 170XX) of miRNA reverse complement initalics.

The ability of AAV2/1-miRNA-Htt 206 and 207 to mediate human huntingtinmRNA reduction was tested in vitro using human embryonic kidney (HEK293)cells. AAV2/1-miRNA-206 and 207 expression plasmids, as well as apositive control plasmid (170XA) containing a miRNA sequence previouslyshown to reduce Htt levels by approximately 50%, were transfected HEK293cells (8 replicates per treatment). Cells were transfected using Fugenetransfection reagent and harvested 48 hours later. Total RNA wasisolated using the TaqMan® Cells-to-CT™ Kit (Ambion). RNA levels weremeasured by quantitative real-time RT-PCR (conducted and analyzed on anABI Prism 7500 Sequence Detector (Applied Biosystems)). Expressionlevels were normalized to human PPIA (peptidylprolyl isomerase). Asshown in FIG. 2, human Htt mRNA levels were reduced followingtransfection with both 206 and 207 plasmids compared to untreateduntreated controls. Level of Htt reduction were nearly equivalentcompared the 170XA positive control.

Example 2: AAV2/1-miRNA-Htt Reduces Htt Expression In Vivo

The ability of AAV2/1-miRNA-206 and 207 to reduce HTT protein levels inthe striatum of YAC128 HD mice was tested. Adult YAC128 mice receivedbilateral intra-striatal injections of AAV2/1-miRNA-Htt 206 (1e10vgs/site) or AAV2/1-miRNA-Htt 207 (1e10 vgs/site), or AAV2/1-CTL3 (anoncoding miRNA control) (1e10 vgs/site). One month following AAVinjection, animals were sacrificed and perfused with PBS. Brains werecollected for histology and biochemical analyses. For biochemicalanalyses the striatal region of one hemisphere was micro-dissected andsnap frozen in liquid nitrogen. Striatal levels of mutant human andmouse Htt mRNA and HTT protein were evaluated by QPCR and Western blotrespectively. Mutant human Htt and mouse Htt mRNA was significantlyreduced in AAV2/1-miRNA-Htt 206 and AAV2/1-miRNA-Htt 207 injected micewhen compared to CTL3 control animals (FIG. 3A). PPIA served as anormalization control gene for all QPCR assays. Mutant human and mouseHTT protein was significantly reduced in all AAV2/1-miRNA-Htt-injectedmice when compared to CTL3 control animals and an equivalent extent ofreduction (approximately 50%, p<0.05) was noted across all treatments(FIG. 3B). Beta-tubulin served as a normalization control gene for allwestern blots.

The effect of AAV2/1-miRNA-Htt 206 and 207 on brain and body weights ofYAC128 mice was evaluated. Animal body weights on the day of surgerywere compared to body weights taken on the day of sacrifice, 1 monthpost injection (FIG. 4A). There were no differences betweenAAV2/1-miRNA-Htt 206 and 207 compared to CTL3 controls. All miceappeared healthy, alert, and responsive one month post treatment and noweight loss was observed in any treatment group. Wet brain wets wererecorded after PBS perfusion and brain dissection. A statisticallysignificant increase in brain weights of YAC128 mice treated withAAV2/1-miRNA-Htt 206 and 207 was observed compared on CTL3 treatedcontrols (FIG. 4B).

Example 3: AAV2/1-miRNA-Htt Corrects Behavioral and CoordinationDeficits in YAC128 Mice

The ability of striatal delivery of AAV2/1-miRNA-Htt-207 to correct theaberrant behavioral phenotypes in YAC128 mice was evaluated. The impactof the AAV2/1-miRNA-Htt 207 mediated reduction of mutant Htt levels onthe well-characterized phenotypic deficits that are present in theYAC128 mouse model of HD was also examined. Age-matched (3 month old)YAC128 and FVB wild-type littermate mice received bilateralintra-striatal injections of either AAV2/1-miRNA-Htt-207 (2e10 vg/site)or AAV2/1-CTL3 control vector (2e10 vgs/site). Mice received behavioraltesting and were sacrificed 3 months after treatment. Western blotanalysis of brain homogenates showed the levels of mutant human HTTprotein was significantly reduced in the striatum ofAAV2/1-miRNA-Htt-207 injected YAC128 and FVB wild-type littermate mice(approximately 50% reduction, p<0.01) when compared toAAV2/1-CTL3-treated controls. Mouse HTT protein levels were notsignificantly reduced in this study (FIGS. 5A and 5B). Real-timequantitative PCR analysis indicated a commensurate reduction in mRNAlevels (FIGS. 5C and 5D).

YAC128 mice have been reported to exhibit motor coordination deficits(which can be revealed using the rotarod test) and a depressivephenotype (which can be revealed using the Porsolt swim test) beginningat 3 months of age (Slow et al., 2003, Van Raamsdonk et al., 2007).Rotarod testing of AAV2/1-CTL3-treated YAC128 mice at 3 monthspost-injection showed significant motor coordination deficits whencompared to AAV2/1-CTL3-treated wild-type littermates (ANOVA, p<0.05)(FIG. 6A). However, YAC128 mice that had been treated withAAV2/1-miRNA-Htt-207 showed performance levels that wereindistinguishable from those of wild-type mice (ANOVA, Tukey's post-hoc;WT 207 vs. YAC128 207, p=NS; WT CTL3 vs. YAC128 CTL3, p<0.05). Hence,partial lowering of mutant Htt levels was sufficient to correct themotor deficits of YAC128 mice. There were no significant differences inrotarod performance between wild-type mice that receivedAAV2/1-miRNA-Htt-207 and wild-type mice that received AAV2/1-CTL3.Previous reports indicated that YAC128 mice exhibit a depressivephenotype that can be detected using the Porsolt swim test (Pouladi etal., 2009). Animals are deemed to exhibit a depressive state if they areimmobile for an extended period when placed into a container of water.Using a basic swim speed test (where swim latency to reach a platformwas measured) researchers have demonstrated that this depressivephenotype in the Porsolt swim test is unrelated to the swimming abilityof YAC128 mice and is independent of the well documented motorcoordination deficits observed in this model (Pouladi et al., 200).Three-month-old YAC128 and WT littermate mice were injected withAAV2/1-miRNA-Htt-207- or AAV2/1-CTL3-vectors and tested 3 months laterin the Porsolt swim test. CTL3 treated YAC128 mice displayed anincreased period of time in an immobile state when compared to eitherAAV2/1-miRNA-Htt-207-treated YAC mice or AAV2/1-CTL3-treated wild-typeanimals (FIG. 6B; ANOVA p<0.05). Again, there were no significantdifferences in the performance of wild-type mice that received eitherAAV2/1-miRNA-Htt or AAV2/1-CTL3. YAC28 mice that had been injected withAAV2/1-miRNA-Htt-207 spent significantly less time in an immobile statethan AAV2/1-CTL3-treated controls. Indeed, the performance ofAAV2/1-miRNA-Htt-207 treated YAC128 mice was similar to that of theirwild-type littermates, suggesting a near-complete correction of thisaberrant phenotype (ANOVA, Tukey's post-hoc; YAC207 vs. YAC CTL3,p<0.05).

The effect of AAV2/1-miRNA-Htt 207 on brain and body weights of YAC128mice was evaluated. Animal body weights on the day of surgery werecompared to body weights taken on the day of sacrifice, 3 months postinjection. There were no differences in body weight betweenAAV2/1-miRNA-Htt 207 treated mice compared to CTL3 treated controls(FIG. 7A). All mice appeared healthy, alert, and responsive three monthspost treatment and no weight loss was observed in any treatment group.Wet brain wets were recorded after PBS perfusion and brain dissection.There were no differences in brain weights of YAC128 mice treated withAAV2/1-miRNA-Htt 207 compared on CTL3 treated controls (FIG. 7B).

Example 4. miRNA's Demonstrate High Guide Activity and Precise 5′Processing Following In Vivo Delivery

YAC128 mice were treated with AAV2/1-miRNA-Htt 206 or AAV2/1-miRNA-Htt207 via intracranial injection. Post-treatment, the striatum wasremoved, and total RNA was isolated. Small RNA sequencing libraries wereconstructed using the NEBNext Small RNA Library Prep Set (New EnglandBiolabs), and sequencing was performed on the Illumina MiSeq instrument.Samples from 2 separate mice were analyzed for each treatment. Here thetotal of all miRNA reads including endogenous sequences are shown aswell as the total guide and passenger reads for each treatment vector.The AAV2/1-miRNA-Htt 202T vector treatment was included in thisexperiment as a control since it had been previously sequenced. Thepercent expected start position for each guide and passenger strandwas >99%, and the 207 vector had high guide: passenger strand ratios of76.1% and 79.3%.

TABLE 2 Guide activity and 5′ processing Vector 202T# 206 207 Sample ID# 202 23 28 33 34 Total Reads* 1,898,745 3,184,602 3,307,273 3,386,1312,599,808 # Total Reads (guide) 47,001 196 186 11,801 39,177 % withinexpected start position 99.1 100 99.5 97.9 97.6 # Total Reads(passenger) 465,981 554 719 3,075 12,327 % within expected startposition 99.2 99.1 99.4 99.5 99.2 % Guide 0.2 26.1 20.6 79.3 79.1

Example 5. Self-Complementary miRHtt207 Vector

The 207 miRHtt expression cassette can be packaged as aself-complementary vector genome. To achieve this, the ITR plasmid isdesigned to be only 2.3 kb in size, this facilitates packaging of a 4.6kb dimeric vector; 4.6 kb is the packaging capacity of an AAV vector.The ITR plasmid can be designed to have a 5′WT ITR and a mutated Ddeleted, truncated 3′ITR (Δ ITR), as depicted in FIG. 8. The predictedvector genomes that could be packaged are the self-complementary vectorgenome, which would be 3165 bp, and would contain a 5′ and 3′ WT ITR anda third, internal, delta ITR (e.g., a chimeric intron). Additionally, itis expected that some monomeric vector genomes would be packaged, andthese would be 1656 bp in size.

An alternative approach to generating a self-complementary AAV miRHtt207 vector i.e., packaging two vector genomes per capsid, would be tomake a small, single stranded, i.e., 1755 bp vector genome, so that twocopies of the vector genome are packaged as a replication intermediatespecies, 3365 bp, (FIG. 9). In this example the ITR plasmid would have a5′ and 3′ WT ITR and the replication intermediate, 3365 bp, would havethree WT ITRs, one 5′ and 3′ and one internal ITR. The single strandedvector gnome species, 1755 bp, could also be packaged.

ADDITIONAL SEQUENCESAll polypeptide sequences are presented as N-terminal to C-terminal unlessindicated otherwise. All nucleic acid sequences are presented as 5′ to 3′unless indicated otherwise. miRNA scaffold DNA sequence (SEQ ID NO: 14)ctggaggcttgctgaaggctgtatgctgttagacaatgattcacacggtgttttggccactgactgacaccgtgtgtcattgtctaacaggacacaaggcctgttactagcactcacatggaacaaatggccVariant AAV ITR for scAAV vectors (SEQ ID NO: 15)CCACTCCCTCTCTGCGCGCTCGCTCGCTCACTGAGGCCGGGCGACCAAAGGTCGCCCGACGCCCGGGCTTTGCCCGGGCGGCCTCAGTGAGCGAGCGAGCGCGCAGAGAGGGA. ssAAV2/1miRHtt.de(SEQ ID NO: 16)TTGGCCACTCCCTCTCTGCGCGCTCGCTCGCTCACTGAGGCCGCCCGGGCAAAGCCCGGGCGTCGGGCGACCTTTGGTCGCCCGGCCTCAGTGAGCGAGCGAGCGCGCAGAGAGGGAGTGGCCAACTCCATCACTAGGGGTTCCTCTATATTACCCTGCTAGGCAATTGGATCCCGGACCGTCGACATTGATTATTGACTAGTTATTAATAGTAATCAATTACGGGGTCATTAGTTCATAGCCCATATATGGAGTTCCGCGTTACATAACTTACGGTAAATGGCCCGCCTGGCTGACCGCCCAACGACCCCCGCCCATTGACGTCAATAATGACGTATGTTCCCATAGTAACGCCAATAGGGACTTTCCATTGACGTCAATGGGTGGAGTATTTACGGTAAACTGCCCACTTGGCAGTACATCAAGTGTATCATATGCCAAGTACGCCCCCTATTGACGTCAATGACGGTAAATGGCCCGCCTGGCATTATGCCCAGTACATGACCTTATGGGACTTTCCTACTTGGCAGTACATCTACGTATTAGTCATCGCTATTACCATGGTCGAGGTGAGCCCCACGTTCTGCTTCACTCTCCCCATCTCCCCCCCCTCCCCACCCCCAATTTTGTATTTATTTATTTTTTAATTATTTTGTGCAGCGATGGGGGCGGGGGGGGGGGGGGGGGGCGCGCCAGGCGGGGCGGGGCGGGGCGAGGGGCGGGGCGGGGCGAGGCGGAGAGGTGCGGCGGCAGCCAATCAGAGCGGCGCGCTCCGAAAGTTTCCTTTTATGGCGAGGCGGCGGCGGCGGCGGGCCTATAAAAAGCGAAGCGCGCGGCGGGCGGGAGTCGCTGCGCGCTGCCTTCGCCCCGTGCCCCGCTCCGCCGCCGCCTCGCGCCGCCCGCCCCGGCTCTGACTGACCGCGTTACTCCCACAGGTGAGCGGGCGGGACGGCCCTTCTCCTCCGGGCTGTAATTAGCGCTTGGTTTAATGACGGCTTGTTTCTTTTCTGTGGCTGCGTGAAAGCCTTGAGGGGCTCCGGGAGGGCCCTTTGTGCGGGGGGAGCGGCTCGGGGGGTGCGTGCGTGTGTGTGTGCGTGGGGAGCGCCGCGTGCGGCTCCGCGCTGCCCGGCGGCTGTGAGCGCTGCGGGCGCGGCGCGGGGCTTTGTGCGCTCCGCAGTGTGCGCGAGGGGAGCGCGGCCGGGGGCGGTGCCCCGCGGTGCGGGGGGGGCTGCGAGGGGAACAAAGGCTGCGTGCGGGGTGTGTGCGTGGGGGGGTGAGCAGGGGGTGTGGGCGCGTCGGTCGGGCTGCAACCCCCCCTGCACCCCCCTCCCCGAGTTGCTGAGCACGGCCCGGCTTCGGGTGCGGGGCTCCGTACGGGGCGTGGCGCGGGGCTCGCCGTGCCGGGCGGGGGGTGGCGGCAGGTGGGGGTGCCGGGCGGGGCGGGGCCGCCTCGGGCCGGGGAGGGCTCGGGGGAGGGGCGCGGCGGCCCCCGGAGCGCCGGCGGCTGTCGAGGCGCGGCGAGCCGGAGCCATTGCCTTTTATGGTAATCGTGCGAGAGGGCGCAGGGACTTCCTTTGTCCCAAATCTGTGCGGAGCCGAAATCTGGGAGGCGCCGCCGCACCCCCTCTAGCGGGCGCGGGGCGAAGCGGTGCGGCGCCGGCAGGAAGGAAATGGGCGGGGAGGGCCTTCGTGCGTCGCCGCGCCGCCGTCCCCTTCTCCCTCTCCAGCCTCGGGGCTGTCCGCGGGGGGACGGCTGCCTTCGGGGGGGACGGGGCAGGGCGGGGTTCGGCTTCTGGCGTGTGACCGGCGGCTCTAGAGCCTCTGCTAACCATGTTCATGCCTTCTTCTTTTTCCTACAGCTCCTGGGCAACGTGCTGGTTATTGTGCTGTCTCATCATTTTGGCAAAGAATTCTTCGAAAGATCTGCTAGCCTGGAGGCTTGCTGAAGGCTGTATGCTGAGTCGGTGTGGTTGACAAGCAGTTTTGGCCACTGACTGACTGCTTGTCCCACACCGACTCAGGACACAAGGCCTGTTACTAGCACTCACATGGAACAAATGGCCATGCATCTAGAGGGCCCTATTCTATAGTGTCACCTAAATGCTAGAGCTCGCTGATCAGCCTCGACTGTGCCTTCTAGTTGCCAGCCATCTGTTGTTTGCCCCTCCCCCGTGCCTTCCTTGACCCTGGAAGGTGCCACTCCCACTGTCCTTTCCTAATAAAATGAGGAAATTGCATCGCATTGTCTGAGTAGGTGTCATTCTATTCTGGGGGGTGGGGTGGGGCAGGACAGCAAGGGGGAGGATTGGGAAGACAATAGCAGGCATGCTGGGGAGCTAGAGTCGACCGGACCGGTGGAAGTCCTCTTCCTCGGTGTCCTTGACTTCAAAGGGTCTCTCCCATTTGCCTGGAGAGAGGGGAAGGTGGGCATCACCAGGGGTGAGTGAAGGTTTGGAAGAGTGTAGCAGAATAAGAAACCATGAGTCCCCTCCCTGAGAAGCCCTGAGCCCCCTTGACGACACACATCCCTCGAGGCTCAGCTTCATCATCTGTAAAAGGTGCTGAAACTGACCATCCAAGCTGCCGAAAAAGATTGTGTGGGGATAATTCAAAACTAGAGGAAGATGCAGAATTTCTACATCGTGGCGATGTCAGGCTAAGAGATGCCATCGTGGCTGTGCATTTTTATTGGAATCATATGTTTATTTGAGGGTGTCTTGGATATTACAAATAAAATGTTGGAGCATCAGGCATATTTGGTACCTTCTGTCTAAGGCTCCCTGCCCCTTGTTAATTGGCAGCTCAGTTATTCATCCAGGGCAAACATTCTGCTTACTATTCCTGAGAGCTTTCCTCATCCTCTAGATTGGCAGGGGAAATGCAGATGCCTGAGCAGCCTCCCCTCTGCCATACCAACAGAGCTTCACCATCGAGGCATGCAGAGTGGACAGGGGCCTCAGGGACCCCTGATCCCAGCTTTCTCATTGGACAGAAGGAGGAGACTGGGGCTGGAGAGGGACCTGGGCCCCCACTAAGGCCACAGCACAGCCAGGACTTTAGCTGTGCTGACTGCACCCTGGCTTGCCTCCACTGCCCTCCTTTGCCTCAAGAGCAAGGGAGCCTCAGAGTGGAGGAAGCAGCCCCTGGCCTTGCCTCCCACCTCCCCTCCCCTATGCTGTTTTCCTGGGACAGTGGGAGCTGGCTTAGAATGCCCTGGGGCCCCCAGGACCCTGGCATTTTAACCCCTCAGGGGCAGGAAGGCAGCCTGAGATACAGAAGAGTCCATCACCTGCTGTATGCCACACACCATCCCCACAGTTACGTACTAGTTCGAAGCCACGCGGACCGTTATAGTTACGAGGAACCCCTAGTGATGGAGTTGGCCACTCCCTCTCTGCGCGCTCGCTCGCTCACTGAGGCCGGGCGACCAAAGGTCGCCCGACGCCCGGGCTTTGCCCGGGCGGCCTCAGTGAGCGAGCGAGCGCGCAGAGAGGGAGTGGCCAAAGATCTmIR207 DNA sequence shown in bold (SEQ ID NO: 17)Stuffer sequence shown in italics (SEQ ID NO: 18) Portion of A1AT gene(SEQ ID NO: 20) aattcgcccttgggc

gccggcagagaaaacatcccagggatttacagatcacatgcaggcagggaccagctcaacccttctttaatgtcatccagggagggggccagggatggaggggaggggttgaggagcgagaggcagttatttttgggtgggattcaccacttttcccatgaagaggggagacttggtattttgttcaatcattaagaagacaaagggtttgttgaacttgacctcgggggggatagacatgggtatggcctctaaaaacatggccccagcagcttcagtccctttctcgtcgatggtcagcacagccttatgcacggcctggaggggagagaagcagagacacgttgtaaggctgatcccaggcctcgagcaaggctcacgtggacacctcccaggaagcgctcactccccctggacggccctggccctgcacatcctctccctccctgtcacataggccttgctcctcctcaaggctttggctgatggggctggctcccctctgtccatcttcctgacaagcgcctctccccctgctcaggtgcacccacaactcagaacagggaagagcatcgtcactccacgtctgcctccagggctctctcctttctagtacacggcttgaagctccttgaggacacggaccctggcagtgaccttcacagtgcccagaccccaagataatgcagccattcatggaactgcaggttgttcattggtcgcctttagttttccaaaataagtgtcactttagctgaaatcattcattaattcagacaccaaatctcacagatcgaaggagtcagaaattcctttgaaacaacttagcccaaacctttctgtgtcagtatggataaatcaaggcccaatgtctagaaggtcttgggcaaagttgaaattcagggtcagtgacacaacctcaagggaggccccgaaagtgccagctgcacagcagcccctgcctggctttgctgtttgcccaccgtcccgtgtcagtgaatcacgggcatcttcaggagctcagcctgggtcttcatttgtttccctcggccccttcctcagcctcaggacagtgctgcagcccccacacattcttccctacagataccatggtgcaacaaggtcgtcagggtgatctcaccttggagagcttcaggggtgcctcctctgtgaccccggagaggtcagccccattgctgaagaccttagtgatgcccagttgacccaggacgctcttcagatcataggttccagtaatggacagtttgggtaaatgtaagctggcagacctgtcgtgcagaaaagaaattcaaggcatggcacagcattcctcttgttcttctgggacccaccacagtgcaagtgttttcttttctgattatttctgccacttactcctgtgtcctccacccacactaagatgggaactcggctttggtttgttctacttttagctcttctacattgagtcaaagaatgttaacatcgaatgaatcacaaaagcttgaaatgccacctcctctgatattctaggtgtcctggaagcctgtctcatcttgccctgtagtgttgggtcacctggcccccagcctgtaacatccccagggccctacacccagagaaacacggggctggtggcagtgcccagtgacaaccgtttagtggataagagaagagtgaccacaccaggctgagtgctcctctctggttttccatggggagacaatgccaccctgagcagggtctggtgtgagcggcagctggctctgggctctctgatccgttaccctctcagcctctttgttctttctcaacccctggagcagagacctcaggaggtgctggcatggaacagagaaattccagcctcgattcctattatgaacccgacaccttttgtattttcatcttggttttacagtgtacaaaacgaactagatcagcagggcatgggcataatcacgaatgcacacacatacactaatgtgtggctcatgtttaagtatcacttactacaggacacccaatctaacagcaccgataaagtgacagagaaacgcaagccttctgcgaacatggcctggctgttccaattccgaaccttgcttttctgggccttgccacacaggctcttcccccgtccccccagggacattctacccttgaactccacactccactgctgcctttgccaggaagcccatctgttcctttttggttctgccagaacgtgtggtggtgctgctgtccctgccttgggcactggatattgggaagggacagtgtccacactggagtgggaagttcccagggacgagacctttacctcctcaccctgggtactgttctcctcatggagcatggacggcgctgcctgaactcagtggtggcctcattctggaagccaagtttatacagagtagcagtgacccagggatgtggggttcaccctcctcagccctctggccagtcctgatgggcctcagtcccaacatggctaagaggtgtgggcagcttcttggtcaccctcaggttggggaatcaccttctgtcttcattttccaggaacttggtgatgatatcgtgggtgagttcatttaccaggtgctgtagtttcccctcatcaggcaggaagaagatggcggtggcattgcccaggtatttcatcagcagcacccagctggacagcttcttacagtgctggatgttaaacatgcctaaacgcttcatcataggcaccttcacggtggtcacctggtccacgtggaagtcctcttcctcggtgtccttgacttcaaagggtctctcccatttgcctggagagaggggaaggtgggcatcaccaggggtgagtgaaggtttggaagagtgtagcagaataagaaaccatgagtcccctccctgagaagccctgagcccccttgacgacacacatccctcgaggctcagcttcatcatctgtaaaaggtgctgaaactgaccatccaagctgccgaaaaagattgtgtggggataattcaaaactagaggaagatgcagaatttctacatcgtggcgatgtcaggctaagagatgccatcgtggctgtgcatttttattggaatcatatgtttatttgagggtgtcttggatattacaaataaaatgttggagcatcaggcatatttggtaccttctgtctaaggctccctgccccttgttaattggcagctcagttattcatccagggcaaacattctgcttactattcctgagagctttcctcatcctctagattggcaggggaaatgcagatgcctgagcagcctcccctctgccataccaacagagcttcaccatcgaggcatgcagagtggacaggggcctcagggacccctgatcccagctttctcattggacagaaggaggagactggggctggagagggacctgggcccccactaaggccacagcagagccaggactttagctgtgctgactgcagcctggcttgcctccactgccctcctttgcctcaagagcaagggagcctcagagtggaggaagcagcccctggccttgcctcccacctcccctcccctatgctgttttcctgggacagtgggagctggcttagaatgccctggggcccccaggaccctggcattttaacccctcaggggcaggaaggcagcctgagatacagaagagtccatcacctgctgtatgccacacaccatccccacagttacgtactagttcgaagccacgcgtccgaagggcgaattStuffer sequence used in some embodiments is underlinedDelta chimeric intron sequence (SEQ ID NO: 21)ggagtcgctgcgcgctgccttcgccccgtgccccgctccgccgccgcctcgcgccgcccgccccggctctgactgaccgcgttactcccacaggtgagcgggcgggacggcccttctcctccgggctgtaattagcgcttggtttaatgacggcttgtttcttttctgtggctgcgtgaaagccttgaggggctccgggagctagagcctctgctaaccatgttcatgccttcttctttttcctacagctcctgggcaacgtgctggttattgtgctgtctcatcsttttggcaaagaattcctcgaagatccggtacccaattccggggccccacgctgcgcatccgcg

What is claimed is:
 1. An RNAi comprising a first strand and a secondstrand, wherein a) the first strand and the second strand form a duplex;b) the first strand comprises a guide region, wherein the guide regioncomprises the nucleic acid sequence 5′-UGGCCGUCCAUCUUGGACCCG-3′ (SEQ IDNO:1) or 5′-AGUCGGUGUGGUUGACAAGCA-3′ (SEQ ID NO:7); and c) the secondstrand comprises a non-guide region.
 2. The RNAi of claim 1, wherein thenucleic the guide region comprises the nucleic acid sequence5′-UGGCCGUCCAUCUUGGACCCG-3′ (SEQ ID NO:1) and the non-guide regioncomprises the sequence 5′-CGGGUCCAAGAUGGACGGCCA-3′ (SEQ ID NO:2).
 3. TheRNAi of claim 2, wherein the first strand comprises a nucleic acidsequence having about 90% identity to SEQ ID NO:1 or about 90% identityto SEQ ID NO:2.
 4. The RNAi of claim 1, wherein the nucleic the guideregion comprises the nucleic acid sequence 5′-AGUCGGUGUGGUUGACAAGCA-3′(SEQ ID NO:7) and the non-guide region comprises the sequence5′-UGCUUGUCAACCACACCGACU-3′ (SEQ ID NO:8).
 5. The RNAi of claim 4,wherein the second strand comprises a nucleic acid sequence having about90% identity to SEQ ID NO:7 or about 90% identity to SEQ ID NO:8.
 6. TheRNAi of any one of claims 1-5, wherein the first strand and the secondstrand are linked by means of a RNA linker capable of forming a loopstructure.
 7. The RNAi of claim 6, wherein the RNA linker comprises from4 to 50 nucleotides.
 8. The RNAi of claim 6 or 7, wherein the loopstructure comprises 4 to 20 nucleotides.
 9. The RNAi of any one ofclaims 6-8, wherein the RNAi comprises 5′ to 3′ the second strand, theRNA linker, and the first strand.
 10. The RNAi of any one of claims 6-8,wherein the RNAi comprises 5′ to 3′ the first strand, the RNA linker,and the second strand.
 11. The RNAi of claim 10, wherein the RNAicomprises the nucleic acid sequence of SEQ ID NO:4 or SEQ ID NO:10. 12.The RNAi of claim 11, wherein the RNAi comprises a nucleotide sequenceabout 90% identical to the nucleotide sequence of SEQ ID NO:4 or SEQ IDNO:
 10. 13. The RNAi of any one of claims 1-12, wherein the RNAi is asmall inhibitory RNA (siRNA), a microRNA (miRNA), or a small hairpin RNA(shRNA).
 14. The RNAi of any one of claims 1-13, wherein the RNAitargets RNA encoding a polypeptide associated with Huntington's disease.15. The RNAi of claim 14, wherein the polypeptide is huntingtin.
 16. TheRNAi of claim 15, wherein the huntingtin comprises a mutation associatedwith Huntington's disease.
 17. An expression construct comprisingnucleic acid encoding the RNAi of any one of claims 1-16.
 18. Theexpression construct of claim 17 wherein the nucleic acid encoding theRNAi comprises a miRNA scaffold.
 19. The expression construct of claim17 or 18, wherein the nucleic acid encoding the RNAi is operably linkedto a promoter.
 20. The expression construct of claim 19, wherein thepromoter is selected from a cytomegalovirus (CMV) immediate earlypromoter, an RSV LTR, a MoMLV LTR, a phosphoglycerate kinase-1 (PGK)promoter, a simian virus 40 (SV40) promoter, a CK6 promoter, atransthyretin promoter (TTR), a TK promoter, a tetracycline responsivepromoter (TRE), an HBV promoter, an hAAT promoter, a LSP promoter, achimeric liver-specific promoter (LSP), an E2F promoter, a telomerase(hTERT) promoter; a cytomegalovirus enhancer/chicken beta-actin/Rabbitβ-globin promoter (CAG) promoter, an elongation factor 1-alpha promoter(EFl-alpha) promoter, a human β-glucuronidase promoter, a chicken3-actin (CBA) promoter, a retroviral Rous sarcoma virus (RSV) LTRpromoter, a dihydrofolate reductase promoter, and a β-actin promoter.21. The expression construct of any one of claims 17-20, wherein theexpression construct further comprises an intron.
 22. The expressionconstruct of claim 21, wherein the intron is a chimeric intron.
 23. Theexpression construct of claim 21, wherein the expression vector is aself-complementary vector and the intron is a delta chimeric intron. 24.The expression construct of any one of claims 17-23, wherein theexpression construct further comprises a polyadenylation signal.
 25. Theexpression construct of claim 24 wherein the polyadenylation signal is abovine growth hormone polyadenylation signal, an SV40 polyadenylationsignal, or a HSV TK pA.
 26. A vector comprising the expression constructof any one of claims 17-25.
 27. The vector of claim 26, wherein thevector is a recombinant adeno-associated virus (rAAV) vector, arecombinant adenoviral vector, a recombinant lentiviral vector or arecombinant herpes simplex virus (HSV) vector.
 28. The vector of claim27, wherein the vector is a recombinant adenoviral vector.
 29. Thevector of claim 28, wherein the recombinant adenoviral vector is derivedfrom Adenovirus serotype 2, 1, 5, 6, 19, 3, 11, 7, 14, 16, 21, 12, 18,31, 8, 9, 10, 13, 15, 17, 19, 20, 22, 23, 24-30, 37, 40, 41, AdHu2, AdHu3, AdHu4, AdHu24, AdHu26, AdHu34, AdHu35, AdHu36, AdHu37, AdHu41,AdHu48, AdHu49, AdHu50, AdC6, AdC7, AdC69, bovine Ad type 3, canine Adtype 2, ovine Ad, or porcine Ad type
 3. 30. The vector of claim 28,wherein the recombinant adenoviral vector is derived from adenovirusserotype 2 or a variant of adenoviral serotype
 5. 31. The vector ofclaim 27, wherein the vector is a recombinant lentiviral vector.
 32. Thevector of claim 31, wherein the recombinant lentiviral vector is derivedfrom a lentivirus pseudotyped with vesicular stomatitis virus (VSV),lymphocytic choriomeningitis virus (LCMV), Ross river virus (RRV), Ebolavirus, Marburg virus, Mokala virus, Rabies virus, RD114 or variantstherein.
 33. The vector of claim 27, wherein the vector is a rHSVvector.
 34. The vector of claim 33, wherein the rHSV vector is derivedfrom rHSV-1 or rHSV-2.
 35. The vector of claim 27, wherein the vector isa rAAV vector.
 36. The rAAV vector of claim 35, wherein the expressionconstruct is flanked by one or more AAV inverted terminal repeat (ITR)sequences.
 37. The rAAV vector of claim 36, wherein the expressionconstruct is flanked by two AAV ITRs.
 38. The rAAV vector of claim 36 or37, wherein the AAV ITRs are AAV1, AAV2, AAV3, AAV4, AAV5, AAV6, AAV7,AAV8, AAVrh8, AAVrh8R, AAV9, AAV10, AAVrh10, AAV11, AAV12, AAV2R471A,AAV DJ, a goat AAV, bovine AAV, or mouse AAV serotype ITRs.
 39. The rAAVvector of any one of claims 36-38, wherein the AAV ITRs are AAV2 ITRs.40. The rAAV vector of any one of claims 36-39, wherein the vectorfurther comprises a stuffer nucleic acid.
 41. The rAAV vector of claim40, wherein the stuffer nucleic acid is located upstream or downstreamof the nucleic acid encoding the RNAi.
 42. The rAAV vector of any one ofclaims 36-41, wherein the vector is a self-complementary rAAV vector.43. The rAAV vector of claim 42, wherein the vector comprises firstnucleic acid sequence encoding the RNAi and a second nucleic acidsequence encoding a complement of the RNAi, wherein the first nucleicacid sequence can form intrastrand base pairs with the second nucleicacid sequence along most or all of its length.
 44. The rAAV vector ofclaim 43, wherein the first nucleic acid sequence and the second nucleicacid sequence are linked by a mutated AAV ITR, wherein the mutated AAVITR comprises a deletion of the D region and comprises a mutation of theterminal resolution sequence.
 45. A cell comprising the vector of anyone of claims 26-35 or the rAAV vector of any one of claims 36-44.
 46. Aviral particle comprising the vector of claim 26, wherein the viralparticle is an AAV particle encapsidating the rAAV vector, an adenovirusparticle encapsidating the recombinant adenoviral vector, a lentiviralparticle encapsidating the recombinant lentiviral vector or an HSVparticle encapsidating the recombinant HSV vector.
 47. The viralparticle of claim 46, wherein the viral particle is an adenovirusparticle encapsidating the recombinant adenoviral vector.
 48. The viralparticle of claim 47, wherein the adenovirus particle comprises a capsidfrom Adenovirus serotype 2, 1, 5, 6, 19, 3, 11, 7, 14, 16, 21, 12, 18,31, 8, 9, 10, 13, 15, 17, 19, 20, 22, 23, 24-30, 37, 40, 41, AdHu2, AdHu3, AdHu4, AdHu24, AdHu26, AdHu34, AdHu35, AdHu36, AdHu37, AdHu41,AdHu48, AdHu49, AdHu50, AdC6, AdC7, AdC69, bovine Ad type 3, canine Adtype 2, ovine Ad, or porcine Ad type
 3. 49. The viral particle of claim48, wherein the adenovirus particle comprises an adenovirus serotype 2capsid or a variant of an adenoviral serotype 5 capsid.
 50. The viralparticle of claim 46, wherein the viral particle is a lentiviralparticle encapsidating the recombinant lentiviral vector.
 51. The viralparticle of claim 50, wherein the lentiviral particle comprises a capsidpseudotyped with vesicular stomatitis virus (VSV), lymphocyticchoriomeningitis virus (LCMV), Ross river virus (RRV), Ebola virus,Marburg virus, Mokala virus, Rabies virus, RD114 or variants therein.52. The viral particle of claim 46, wherein the viral particle is a HSVparticle.
 53. The viral particle of claim 52, wherein the HSV particleis a rHSV-1 particle or a rHSV-2 particle.
 54. A recombinant AAVparticle comprising the rAAV vector of any one of claims 36-44.
 55. TherAAV particle of claim 54, wherein the AAV viral particle comprises anAAV1, AAV2, AAV3, AAV4, AAV5, AAV6, AAV7, AAV8, AAVrh8, AAVrh8R, AAV9,AAV10, AAVrh10, AAV11, AAV12, AAV2R471A, AAV2/2-7m8, AAV DJ, AAV2 N587A,AAV2 E548A, AAV2 N708A, AAV V708K, AAV2-HBKO, AAVDJ8, AAVPHP.B,AAVPHP.eB, AAVBR1, AAVHSC15, AAVHSC17, a goat AAV, AAV1/AAV2 chimeric,bovine AAV, or mouse AAV capsid rAAV2/HBoV1 serotype capsid.
 56. TherAAV particle of claim 54 or 55, wherein the ITR and the capsid of therAAV viral particle are derived from the same AAV serotype.
 57. The rAAVparticle of claim 54 or 55, wherein the ITR and the capsid of the rAAVviral particle are derived from different AAV serotypes.
 58. The rAAVparticle of claim 57, wherein the ITR is derived from AAV2 and thecapsid of the rAAV particle is derived from AAV1.
 59. A compositioncomprising the viral particle of any one of claims 41-50 or the rAAVparticle of any one of claims 54-58.
 60. The composition of claim 59,wherein the composition further comprises a pharmaceutically acceptablecarrier.
 61. A kit comprising the RNAi of any one of claims 1-16.
 62. Akit comprising the viral particle of any one of claims 44-53 or the AAVparticle of any one of claims 54-58.
 63. A kit comprising thecomposition of claim 59 or
 60. 64. The kit of any one of claims 61-63,further comprising instructions for use.
 65. A method for treatingHuntington's disease in a mammal comprising administering to the mammalan RNAi comprising a first strand comprising a first nucleic acidcomprising the sequence 5′-UGGCCGUCCAUCUUGGACCCG-3′ (SEQ ID NO:1) and asecond strand comprising a second nucleic acid comprising the sequence5′-CGGGUCCAAGAUGGACGGCCA-3′ (SEQ ID NO:2) or a first strand comprising afirst nucleic acid comprising the sequence 5′-AGUCGGUGUGGUUGACAAGCA-3′(SEQ ID NO:7) and a second strand comprising a second nucleic acidcomprising the sequence 5′-UGCUUGUCAACCACACCGACU-3′ (SEQ ID NO:8).
 66. Amethod for inhibiting the expression of htt in a mammal withHuntington's disease comprising administering to the mammal an RNAicomprising a first strand comprising a first nucleic acid comprising thesequence 5′-UGGCCGUCCAUCUUGGACCCG-3′ (SEQ ID NO:1) and a second strandcomprising a second nucleic acid comprising the sequence5′-CGGGUCCAAGAUGGACGGCCA-3′ (SEQ ID NO:2) or a first strand comprising afirst nucleic acid comprising the sequence 5′-AGUCGGGUGUGGUUGACAAGCA-3′(SEQ ID NO:7) and a second strand comprising a second nucleic acidcomprising the sequence 5′-UGCUUGUCAACCACACCGACU-3′ (SEQ ID NO:8).
 67. Amethod for inhibiting the accumulation of htt in a cell of a mammal withHuntington's disease comprising administering to the mammal an RNAicomprising a first strand comprising a first nucleic acid comprising thesequence 5′-UGGCCGUCCAUCUUGGACCCG-3′ (SEQ ID NO:1) and a second strandcomprising a second nucleic acid comprising the sequence5′-CGGGUCCAAGAUGGACGGCCA-3′ (SEQ ID NO:2) or a first strand comprising afirst nucleic acid comprising the sequence 5′-AGUCGGUGUGGUUGACAAGCA-3′(SEQ ID NO:7) and a second strand comprising a second nucleic acidcomprising the sequence 5′-UGCUUGUCAACCACACCGACU-3′ (SEQ ID NO:8). 68.The method of any one of claims 65-67, wherein the first strandcomprises a nucleic acid sequence having about 90% identity to SEQ IDNO:1 or about 90% identity to SEQ ID NO:7.
 69. The method of any one ofclaims 65-67, wherein the second strand comprises a nucleic acidsequence having about 90% identity to SEQ ID NO:2 or about 90% identityto SEQ ID NO:8.
 70. The method of any one of claims 65-69, wherein thefirst strand and the second strand are linked by means of a RNA linkercapable of forming a loop structure.
 71. The method of claim 70, whereinthe RNA linker comprises from 4 to 50 nucleotides.
 72. The method ofclaim 71 or 71, wherein the loop structure comprises 4 to 20nucleotides.
 73. The method of any one of claims 70-72, wherein the RNAicomprises 5′ to 3′ the second strand, the RNA linker, and the firststrand.
 74. The method of any one of claims 70-72, wherein the RNAicomprises 5′ to 3′ the first strand, the RNA linker, and the secondstrand.
 75. The method of claim 74, wherein the RNAi comprises thenucleic acid sequence of SEQ ID NO:4 or SEQ ID NO:10.
 76. The method ofclaim 74, wherein the RNAi comprises a nucleotide sequence about 90%identical to the nucleotide sequence of SEQ ID NO:4 or SEQ ID NO:10. 77.The method of any one of claims 65-76, wherein the RNAi is encoded on anexpression construct.
 78. The method of any one of claims 65-77, whereinthe nucleic acid encoding the RNAi comprises a miRNA scaffold.
 79. Themethod of any one of claims 65-78, wherein the nucleic acid encoding theRNAi is operably linked to a promoter.
 80. The method of claim 79,wherein the promoter is capable of expressing the RNAi in the brain of amammal.
 81. The method of claim 80, wherein the promoter is selectedfrom a cytomegalovirus (CMV) immediate early promoter, a RSV LTR, aMoMLV LTR, a phosphoglycerate kinase-1 (PGK) promoter, a simian virus 40(SV40) promoter, a CK6 promoter, a transthyretin promoter (TTR), a TKpromoter, a tetracycline responsive promoter (TRE), an HBV promoter, anhAAT promoter, a LSP promoter, a chimeric liver-specific promoter (LSP),a E2F promoter, a telomerase (hTERT) promoter; a cytomegalovirusenhancer/chicken beta-actin/Rabbit β-globin (CAG) promoter, anelongation factor 1-alpha promoter (EFl-alpha) promoter and a humanβ-glucuronidase promoter.
 82. The method of any one of claims 79-81,wherein the promoter is a hybrid chicken β-actin promoter (CBA)comprising a CMV enhancer and a chicken β-actin promoter.
 83. The methodof any one of claims 77-82, wherein the expression cassette furthercomprises an intron.
 84. The method of claim 83, wherein the intron is achimeric intron.
 85. The method of claim 83, wherein the expressioncassette is a self-complementary vector and the intron is a deltachimeric intron.
 86. The method of any one of claims 77-85, wherein thenucleic acid further comprises a polyadenylation signal.
 87. The methodof claim 86, wherein the polyadenylation signal is a bovine growthhormone polyadenylation signal.
 88. The method of any one of claims77-87, wherein the expression construct is encoded by a vector.
 89. Themethod of claim 88, wherein the vector is a recombinant adeno-associatedvirus (rAAV) vector, a recombinant adenoviral vector, a recombinantlentiviral vector or a recombinant herpes simplex virus (HSV) vector.90. The method of claim 89, wherein the vector is a recombinantadenoviral vector.
 91. The method of claim 90, wherein the recombinantadenoviral vector is derived from Adenovirus serotype 2, 1, 5, 6, 19, 3,11, 7, 14, 16, 21, 12, 18, 31, 8, 9, 10, 13, 15, 17, 19, 20, 22, 23,24-30, 37, 40, 41, AdHu2, AdHu 3, AdHu4, AdHu24, AdHu26, AdHu34, AdHu35,AdHu36, AdHu37, AdHu41, AdHu48, AdHu49, AdHu50, AdC6, AdC7, AdC69,bovine Ad type 3, canine Ad type 2, ovine Ad, or porcine Ad type
 3. 92.The method of claim 91, wherein the recombinant adenoviral vector isderived from adenovirus serotype 2 or a variant of adenoviral serotype5.
 93. The method of claim 89, wherein the vector is a recombinantlentiviral vector.
 94. The method of claim 93, wherein the recombinantlentiviral vector is derived from a lentivirus pseudotyped withvesicular stomatitis virus (VSV), lymphocytic choriomeningitis virus(LCMV), Ross river virus (RRV), Ebola virus, Marburg virus, Mokalavirus, Rabies virus, RD114 or variants therein.
 95. The method of claim89, wherein the vector is a rHSV vector.
 96. The method of claim 95,wherein the rHSV vector is derived from rHSV-1 or rHSV-2.
 97. The methodof claim 89, wherein the vector is a recombinant AAV (rAAV) vector. 98.The method of claim 97, wherein the expression construct is flanked byone or more AAV inverted terminal repeat (ITR) sequences.
 99. The methodof claim 98, wherein the expression construct is flanked by two AAVITRs.
 100. The method of claim 98 or 99, wherein the AAV ITRs are AAVITRs are AAV1, AAV2, AAV3, AAV4, AAV5, AAV6, AAV7, AAV8, AAVrh8,AAVrh8R, AAV9, AAV10, AAVrh10, AAV11, AAV12, AAV2R471A, AAV DJ, a goatAAV, bovine AAV, or mouse AAV serotype ITRs.
 101. The method of any oneof claims 98-100, wherein the AAV ITRs are AAV2 ITRs.
 102. The method ofclaim 101, wherein the rAAV vector comprises 5′ to 3′ an AAV2 ITR, apromoter, an intron, nucleic acid encoding the RNAi, a polyadenylationsignal, and an AAV2 ITR.
 103. The method of claim 102, wherein thepromoter is a CBA promoter.
 104. The method of claim 102, wherein theintron is a chimeric intron, a delta chimeric intron or an abbreviatedchimeric intron.
 105. The method of any one of claims 102-104, whereinthe polyadenylation signal is a bovine growth hormone polyadenylationsignal.
 106. The method of claim 101, wherein the rAAV vector comprises5′ to 3′ an AAV2 ITR, the CBA promoter, a chimeric intron, nucleic acidencoding the RNAi, a bovine growth hormone polyadenylation signal, andan AAV2 ITR.
 107. The method of claim 106, wherein the vector furthercomprise a stuffer nucleic acid.
 108. The method of claim 107, whereinthe stuffer nucleic acid further comprises nucleic acid encoding areporter polypeptide.
 109. The method of claim 107 or 108, wherein thestuffer nucleic acid is located upstream or downstream of the nucleicacid encoding the RNAi.
 110. The method of any one of claims 97-109,wherein the vector is a self-complementary vector.
 111. The method ofclaim 110, wherein the vector comprises first nucleic acid sequenceencoding the RNAi and a second nucleic acid sequence encoding acomplement of the RNAi, wherein the first nucleic acid sequence can formintrastrand base pairs with the second nucleic acid sequence along mostor all of its length.
 112. The method of claim 111, wherein the firstnucleic acid sequence and the second nucleic acid sequence are linked bya mutated AAV ITR, wherein the mutated AAV ITR comprises a deletion ofthe D region and comprises a mutation of the terminal resolutionsequence.
 113. The method of claim 88 or 89, wherein the vector isencapsidated in a rAAV particle, the recombinant adenovirus vector isencapsidated in an adenoviral particle, the recombinant lentiviralvector is encapsidated in a lentiviral particle or the recombinant HSVvector is encapsidated in a HSV.
 114. The method of claim 113, whereinthe viral particle is an adenovirus particle encapsidating therecombinant adenoviral vector.
 115. The method of claim 114, wherein theadenovirus particle comprises a capsid from Adenovirus serotype 2, 1, 5,6, 19, 3, 11, 7, 14, 16, 21, 12, 18, 31, 8, 9, 10, 13, 15, 17, 19, 20,22, 23, 24-30, 37, 40, 41, AdHu2, AdHu 3, AdHu4, AdHu24, AdHu26, AdHu34,AdHu35, AdHu36, AdHu37, AdHu41, AdHu48, AdHu49, AdHu50, AdC6, AdC7,AdC69, bovine Ad type 3, canine Ad type 2, ovine Ad, or porcine Ad type3.
 116. The method of claim 115, wherein the adenovirus particlecomprises an adenovirus serotype 2 capsid or a variant of an adenoviralserotype 5 capsid.
 117. The method of claim 113, wherein the viralparticle is a lentiviral particle encapsidating the recombinantlentiviral vector.
 118. The method of claim 117, wherein the lentiviralparticle comprises a capsid pseudotyped with vesicular stomatitis virus(VSV), lymphocytic choriomeningitis virus (LCMV), Ross river virus(RRV), Ebola virus, Marburg virus, Mokala virus, Rabies virus, RD114 orvariants therein.
 119. The method of claim 113, wherein the viralparticle is a HSV particle.
 120. The method of claim 119, wherein theHSV particle is a rHSV-1 particle or a rHSV-2 particle.
 121. The methodof claim 113, wherein the viral particle is a recombinant AAV particle.122. The method of claim 121, wherein the AAV viral particle comprisesan AAV1, AAV2, AAV3, AAV4, AAV5, AAV6, AAV7, AAV8, AAVrh8, AAVrh8R,AAV9, AAV10, AAVrh10, AAV11, AAV12, AAV2R471A, AAV2/2-7m8, AAVDJ8, AAV2N587A, AAV2 E548A, AAV2 N708A, AAV2 V708K, AAV2-HBKO, AAVDJ8, AAVPHP.B,AAVPHP.eB, AAVBR1, AAVHSC15, AAVHSC17, goat AAV, AAV1/AAV2 chimeric,bovine AAV, mouse AAV, or rAAV2/HBoV1 serotype capsid.
 123. The methodof claim 121 or 122, wherein the ITR and the capsid of the rAAV viralparticle are derived from the same AAV serotype.
 124. The method ofclaim 121 or 122, wherein the ITR and the capsid of the rAAV viralparticles are derived from different AAV serotypes.
 125. The method ofany one of claims 121-124, wherein the rAAV viral particle comprisesAAV2 capsid.
 126. The method of claim 125, wherein the rAAV viralparticle comprises an AAV1 capsid, and wherein the vector comprises AAV2ITRs.
 127. A method of any one of claims 65-112, wherein the viralparticle of any one of claims 113-120 or the rAAV particle of any one ofclaims 121-126 is in a composition.
 128. The method of claim 127,wherein the composition further comprises a pharmaceutically acceptablecarrier.